Answer: B
Explanation:
The y component of the vector is given by the formula:
y component = magnitude of the vector x sin(angle between the vector and the y-axis)
In this case, the magnitude of the vector is 120 N and the angle between the vector and the y-axis is 50 degrees. So we have:
y component = 120 N x sin(50°) ≈ 92 N
Therefore, the answer is (B) 92 N.
Two trains are moving in the same direction on parallel tracks. Train A is 300 m long and moves at 10 m/s. Train B is 250 m long and moves at 8 m/s. The front of train B is 1 km ahead of the front of train A. How far does Train A travel while both trains overlap?
Train A travels 3,200 meters while both trains (moving in the same direction on parallel tracks) overlap.
To find the distance Train A travels while both trains (on parallel tracks) overlap, we need to:-
1. Determine the relative speed of Train A with respect to Train B. Since both trains are moving in the same direction, we can find this by subtracting the speed of Train B from the speed of Train A: 10 m/s - 8 m/s = 2 m/s.
2. Calculate the initial distance between the two trains. The front of Train B is 1 km (1,000 m) ahead of Train A. Therefore, the distance between the back of Train B and the front of Train A is 1,000 m - 250 m = 750 m.
3. Find the time taken for Train A to catch up with Train B. Divide the initial distance by the relative speed: 750 m / 2 m/s = 375 seconds.
4. Calculate the distance traveled by Train A while both trains overlap. During the overlap, Train A is moving at 10 m/s, so multiply its speed by the time taken to catch up with Train B: 10 m/s * 375 seconds = 3,750 meters.
5. Calculate the overlap distance. The combined length of both trains is 300 m + 250 m = 550 m. Since Train A catches up with Train B, the distance it travels while overlapping is the combined length of both trains: 3,750 m - 550 m = 3,200 meters.
Therefore, Train A travels 3,200 meters while both trains overlap.
Learn more about the direction: https://brainly.com/question/3184914
#SPJ11
determine the current (in ma) through the led in the circuit below if the forward biased voltage of the led is 2 v?
The current flowing through the LED is also 10 mA. To determine the current (in mA) through the LED in the circuit given below.
Assuming that the forward biased voltage of the LED is 2V, the following procedure is followed: To calculate the current flowing through the LED in the given circuit, the following formula is used: Ohm's Law: V = IR where V is the voltage applied to the circuit, I is the current flowing through the circuit, and R is the resistance of the circuit. Now, in the given circuit, the total voltage applied to the circuit is 12V. Therefore, the voltage across the resistor (R) is V = 12 - 2 = 10V. So, we know that the voltage across the resistor is 10V and the value of the resistor is 1000 ohms.
Therefore, the current through the resistor is: I = V/R = 10/1000 = 0.01 A = 10 mA. Now, this current will also be the current flowing through the LED as the LED is in series with the resistor. Therefore, the answer is 10 mA.
Learn more about Ohm's Law : https://brainly.com/question/231741
#SPJ11
a stone and a block are on an incline as shown in figure. the stone is at rest. how many forces act on the stone?
These two forces act on the stone:
Force due to gravityForce of the inclineThe stone in the figure shown is at rest, which means that the net force on the stone is zero. Therefore, there must be two forces acting on the stone, one in the direction of the incline and the other in the opposite direction. These two forces are:
Force due to gravity (weight): This is the force of gravity acting on the stone in the downward direction. This force is equal to the weight of the stone and opposes the force of the incline.The force of the incline: This is the force of the incline acting on the stone in the upward direction. This force is equal to the weight of the stone and is the opposite of the force due to gravity.Learn more about the force of gravity: https://brainly.com/question/29236134
#SPJ11
how long does it take to accelerate to 60 mph ? your answer, which seems impossibly short, is confirmed by track tests.
It takes around 5 seconds to accelerate to 60 mph.
1. What is acceleration?
Acceleration is the process of increasing speed or velocity over time. When a car accelerates, it gradually increases its velocity from a standstill to a faster speed.
As a result, acceleration can be measured in units of distance over time, such as meters per second squared (m/s2) or miles per hour per second (mph/s).
Acceleration is an important concept in physics and engineering, as it helps to describe the motion of objects in terms of their speed, direction, and rate of change. In addition, acceleration is often used in the design of cars, aircraft, and other vehicles, as it can affect their performance and fuel efficiency.
Learn more about mph here:
https://brainly.com/question/16882321#
#SPJ11
suppose you are standing on a train accelerating at 0.30 g . part a what minimum coefficient of static friction must exist between your feet and the floor if you are not to slide?
When standing on a train accelerating at 0.30 g, there is an effective force acting on you due to the acceleration. This force is equivalent to the force that would be experienced by an object with mass m = your mass under the influence of gravity and this force is resisted by the static friction force:
F = m * a
where a is the acceleration of the train and g is the acceleration due to gravity (approx. 9.81 m/s^2).
To avoid sliding on the floor of the train, the static friction force between your feet and the floor must be greater than or equal to the force due to the acceleration of the train. Therefore, we have:
f_s >= m * a
where f_s is the static friction force.
The maximum static friction force that can act between your feet and the floor is given by:
f_s = μ_s * N
where μ_s is the coefficient of static friction between your feet and the floor, and N is the normal force acting on your feet.
Since you are standing still relative to the train, the normal force acting on your feet is equal to your weight, which we can express as:
N = m * g
Substituting this into the expression for the maximum static friction force, we get:
f_s = μ_s * m * g
Substituting this expression for f_s into the inequality above, we get:
μ_s * m * g >= m * a
Simplifying this expression, we get:
μ_s >= a / g
Substituting a = 0.30 g and g = 9.81 m/s^2, we get:
μ_s >= 0.30
Therefore, the minimum coefficient of static friction that must exist between your feet and the floor to avoid sliding on the train is 0.30.
Learn more about static friction:
https://brainly.com/question/22438157
#SPJ11
always tangent to the track, causes the car to speed up as it goes around. if it starts from rest, its speed at the end of one revolution is:
The force that is always tangent to the track and causes the car to speed up as it goes around is known as the centripetal force.
The force that acts on a body moving in a circular path toward the center of the circle or curve is known as the centripetal force.
If an object moves in a circular path, the direction of the velocity changes, and it is, therefore, an accelerated motion.
Tangential velocity is the velocity of an object that moves in a circular path at any given point in the circle. If the car begins from rest, the only velocity is tangential velocity.
Therefore, if the car begins from rest, its velocity is at the end of one revolution around the circular track with a speed.
Learn more about centripetal force here:
https://brainly.com/question/898360
#SPJ11
what is the magnitude and direction of the force on the vertical wire segment on the left side of the square? the magnitude should be written in terms of i, l, and b, or could be zero, and the choices of direction are: left, right, up, down, in, out.
The magnitude of the force on the vertical wire segment on the left side of the square is F = (b * i * l) / 2, and the direction is out by Fleming's left-hand rule.
This is calculated by applying the equation for the force on a wire in a uniform magnetic field: F = (B * I * l) / 2. Here, B is the magnitude of the magnetic field, I is the current running through the wire, and l is the length of the wire.
The magnitude and direction of the force on the vertical wire segment on the left side of the square are as follows. Magnitude of force
The magnetic force on the wire can be calculated using the equation
F = BILsinθ
Where, F is the magnetic force, B is the magnetic field, I is the current in the wire, L is the length of the wireθ is the angle between the direction of the magnetic field and the direction of the current. In this case, the angle between the direction of the magnetic field and the direction of the current is 90°.
Hence, sin 90° = 1.So,F = BIL
Direction of force The direction of the magnetic force can be determined by Fleming's left-hand rule, which states that if you point your forefinger in the direction of the magnetic field and your middle finger in the direction of the current, your thumb will point in the direction of the force.
In this case, the magnetic field is pointing into the page, and the current is flowing from top to bottom. So, if you point your forefinger into the page and your middle finger downwards, your thumb will point towards the left side of the square. Therefore, the direction of the force is left.
For more such questions on Fleming's left-hand rule , Visit:
https://brainly.com/question/29054378
#SPJ11
radiative energy is: group of answer choices energy used to power home radiators. energy carried by light. energy from nuclear power plants. energy of motion. heat energy.
Radiative energy is the energy carried by light.
What is radiative energy?
Radiative energy is the energy carried by light. It is a form of energy that can be transmitted through space without requiring a medium for it to move through. Radiative energy can come from natural sources like the sun or artificial sources like light bulbs.
Radiative energy is important for a variety of reasons. For one thing, it is the primary source of energy for many living organisms on Earth, particularly plants. Energy from the sun helps plants photosynthesize and produce food that they can use to grow and reproduce.
Radiative energy is also important for human life. It is used in a variety of ways, including in the form of light for illuminating spaces and in the form of heat for cooking and keeping warm. Understanding the nature and properties of radiative energy is important for a wide range of scientific and technological fields.
To know more about radiative energy:
https://brainly.com/question/15698443
#SPJ11
suppose you stare at a static red square for two minutes. you then move your eyes back and forth across a white wall. what do opponent-process theory and corollary discharge theory predict you will experience?
Both the opponent-process theory and the corollary discharge theory predict a complementary color aftereffect when you shift your gaze to the white wall.
Suppose you stare at a static red square for two minutes, you then move your eyes back and forth across a white wall. The Opponent-process theory and corollary discharge theory predict you will experience a complementary color aftereffect when you shift your gaze to the white wall. The opponent-process theory suggests that cells in the visual system respond to complementary color pairs such as green and red, yellow and blue, and white and black. The cells work in opposition, with one group exciting and the other inhibiting. When the cells become fatigued due to prolonged exposure to a color, the cells' firing rates adjust, causing an opponent color to become more sensitive.
Cone cells adapt to changes in visual stimuli and return to their baseline firing rates, which is known as adaptation. The visual system responds in the opposite direction after adaptation to a stimulus, causing a complementary color aftereffect. This effect causes a red afterimage when you look away from a green stimulus or a green afterimage when you look away from a red stimulus. The corollary discharge theory explains how the brain anticipates the sensory consequences of a motor act. In the human body, a motor command is given by the brain, which then sends a copy of that command to the visual system.
The visual system anticipates the motion of the object that is being tracked and removes the motion that results from the eye's movement, allowing the object's motion to remain stable on the retina even though the eye is moving. When the eye's movement is blocked, the motion's removal causes an illusion of movement in the opposite direction, known as a motion aftereffect. Thus, both the opponent-process theory and the corollary discharge theory predict a complementary color aftereffect when you shift your gaze to the white wall.
Learn more about Theory
brainly.com/question/14543764
#SPJ11
what was the ratio of a weight to its just noticeable difference weight when they were lifted what was the ratio of a weight to its just noticeable difference weight when the weight were placed in the subject's hands?
According to Weber's Law, the ratio of a weight to its just noticeable difference weight when placed in the subject's hands is 1 : 40.
The ratio of a weight to its just noticeable difference weight when it is lifted by a subject is 1 : 40. This implies that if the weight of an object is x, the minimum additional weight that can be added to it and be noticed by a subject is x/40.The ratio of a weight to its just noticeable difference weight when the weight is placed in the subject's hands is 1:20.
This implies that if the weight of an object is x, the minimum additional weight that can be added to it and be noticed by a subject when it is placed in their hands is x/20. The Weber-Fechner Law applies in this scenario. It is a relationship between the intensity of a stimulus and its perceived strength that states that the sensation is proportional to the logarithm of the stimulus' intensity.
Learn more about Weber's Law at https://brainly.com/question/19021235
#SPJ11
on a coordinate plane, vector v has a magnitude of 6 miles per hour in a northwesterly direction. what are the magnitude and direction of
Vector V is a vector with a magnitude of 6 miles per hour in a northwesterly direction on the coordinate plane. The magnitude of vector V is 6, and its direction is northwesterly.
What are the magnitude and direction of vector?cos θ = x / r, sin θ = y / r,
tan θ = y / x,
where θ is the angle between the vector and the x-axis, x and y are the coordinates of the vector on the coordinate plane, and r is the magnitude of the vector.
The magnitude of vector V: The magnitude of vector V is 6 miles per hour.
Therefore, r = 6.
The direction of vector V: the angle θ, the x and y components of vector V must be determined.
The angle between vector V and the x-axis is 45 degrees since the vector is going northwesterly, so the angle is halfway between 90 degrees for directly up and 0 degrees for directly to the right. Because the angle is 45 degrees, the x and y components are equal.
Therefore, the x and y components are both 6 / √2. Using
cos θ = x / r and sin θ = y / r,
The values of cos θ and sin θ.cos θ
= 6 / √2 / 6
= 1 / √2, and
sin θ = 6 / √2 / 6
= 1 / √2.
Since cos θ = 1 / √2 and sin θ = 1 / √2, θ
= 45 degrees.
Tan θ = y / x
= 1 / 1, so θ
= tan⁻¹(1)
= 45 degrees.
Therefore, the magnitude of vector V is 6, and its direction is northwesterly.
To know more about vectors:
https://brainly.com/question/12937011
#SPJ11
if one object has twice as much mass as another object, it also has twice as much inertia. volume. acceleration due to gravity. velocity. all of these
If one object has twice as much mass as another object, it also has twice as much inertia. The correct answer is "inertia".
What is inertia?Inertia is the reluctance of an object to alter its condition of motion or rest. The more massive an object is, the more difficult it is to move. As a result, an object with a larger mass has a greater tendency to retain its current state of motion. This trait of an object is referred to as inertia.
The mass of an object has an impact on its inertia. The more mass an object has, the greater its inertia is. When two objects of different masses are subjected to a force, the less massive object will accelerate more quickly than the more massive one. This is the result of the inertia of the more massive object.
Along with mass, the other given options - volume, acceleration due to gravity, and velocity - do not have a direct impact on the inertia of an object. Velocity is related to momentum, and acceleration due to gravity is related to weight, but neither of these concepts affects inertia. Hence, the correct option is inertia.
Learn more about inertia at https://brainly.com/question/1140505
#SPJ11
An empty beer can has a mass of 50 g, a length of 12 cm, and a radius of 3.3 cm. Assume that the shell of the can is a perfect cylinder of uniform density and thickness.
(a) What is the mass of the lid/bottom?
(b) What is the mass of the shell?
(c) Find the moment of inertia of the can about the cylinder's axis of symmetry.
Empty beer can: mass 50g, length 12cm, radius 3.3cm. Moment of inertia found by subtracting mass of lid/bottom from mass of empty can, and using I=(1/2)mr² for a solid cylinder. Result: 1.7 x 10^-5 kg m².
An empty beer can has a mass of 50 g, a length of 12 cm, and a radius of 3.3 cm. Assume that the shell of the can is a perfect cylinder of uniform density and thickness. To find the moment of inertia of the can about the cylinder's axis of symmetry-
(a) Let the mass of the lid/bottom be m. The mass of the empty can is 50g.
Since the lid and bottom are identical in shape and mass, we can write that the total mass of the can is 2m + 50g.
Thus, the mass of the lid/bottom is m = (50g)/2 = 25g.
Therefore, the mass of the lid/bottom is 25g.
(b) The mass of the shell is the mass of the empty can minus the mass of the lid/bottom.
Therefore, the mass of the shell is
[tex]m_{shell} = m_{empty} - m_{lid/bottom} = 50g - 25g = 25g.[/tex]
(c) Moment of inertia of a solid cylinder of radius r and mass m about the axis of symmetry is given by
I = (1/2)mr²
The radius of the can is r = 3.3 cm = 0.033 m.
The length of the can is not needed to find the moment of inertia of the can about its axis of symmetry since the moment of inertia is independent of the length of the cylinder (as long as its mass and radius remain the same).
The mass of the shell is m_shell = 25g = 0.025 kg.
Using the formula for moment of inertia, we get
[tex]I = (1/2)mr² = (1/2)(0.025 kg)(0.033 m)² = 1.7 x 10^-5 kg m²[/tex]
Therefore, the moment of inertia of the can about its axis of symmetry is 1.7 x 10^-5 kg m².
Read about moment of inertia: https://brainly.com/question/14119750
#SPJ11
if a disk in the lower spine supports half the weight of a 72 kg person, by how many mm does the disk compress?
The disk in the lower spine that supports half the weight of a 72 kg person compresses by 0.18 mm.
To calculate the compression of the disk, we can use the formula for the compression of a cylinder under axial load:
ΔL/L = F/(A*E)
Where ΔL is the change in length of the cylinder, L is the original length, F is the force applied, A is the cross-sectional area, and E is Young's modulus.
In this case, the force on the disk is half the weight of the person, which is (1/2)72 kg9.81 m/s² = 353.16 N. The cross-sectional area of the disk is (π/4)*(0.04 m)² = 0.00126 m².
Plugging in these values and the given Young's modulus, we get:
ΔL/L = (353.16 N)/(0.00126 m² * 1.0 × 10⁶ N/m²) = 0.28 × 10⁻³
Multiplying by the original thickness of the disk (5.0 mm), we get the compression of the disk:
ΔL = 0.28 × 10⁻³* 5.0 × 10⁻² m = 0.14 × 10⁻⁴ m = 0.18 mm.
Therefore, the cartilage disk located in the lower spine that sustains 50% of the weight of a person weighing 72 kg will experience a compression of 0.18 mm.
The complete question is: There is a disk of cartilage between each pair of vertebrae in your spine. Young's modulus for cartilage is 1.0 × 106N/m². Suppose a relaxed disk is 4.0 cm in diameter and 5.0 mm thick. If a disk in the lower spine supports half the weight of a 72 kg person, by how many mm does the disk compress?
To know more about compresses, refer here:
https://brainly.com/question/31084499#
#SPJ11
What is the transfer of thermal energy called?
Answer:
Conduction
Explanation:
The process by which heat energy is transmitted through collisions between neighboring atoms
if a 2000-kg car traveling at 30 m/s hits a wall and comes to a complete stop in 0.03 seconds, how much force was applied to the car?
If a 2000-kg car traveling at 30 m/s hits a wall and comes to a complete stop in 0.03 seconds the force that was applied to the car is 6,000,000 N
The force applied to the car can be calculated using the formula:
Force = (mass x change in velocity) / time
Here, the mass of the car is 2000 kg, the initial velocity is 30 m/s, the final velocity is 0 m/s (since the car comes to a complete stop), and the time taken is 0.03 seconds.
Substituting these values, we get:
Force = (2000 kg x (0 m/s - 30 m/s)) / 0.03 s
Force = -6,000,000 N
The negative sign indicates that the force is acting in the opposite direction to the motion of the car. So, the force applied to the car by the wall is 6,000,000 N.
Learn more about force at
https://brainly.com/question/13191643
#SPJ4
is there an advantage to following through when hitting a baseball with a bat, thereby maintaining a longer contact between the bat and the ball?
Yes, there is an advantage to following through when hitting a baseball with a bat, thereby maintaining a longer contact between the bat and the ball.
The advantage of following through in a baseball game is that it increases the speed of the ball and also the energy associated with the ball's trajectory.
The longer the bat comes in contact with the ball, the greater the energy stored in the ball, and the farther the ball will go. Therefore, it is very important to follow through while hitting the ball with the bat in baseball games, which will result in the ball being propelled much farther than if it had been hit with a minimal follow-through.
Thus, it is beneficial to follow through when hitting a baseball with a bat, thereby maintaining a longer contact between the bat and the ball.
To know more about "energy": https://brainly.com/question/30041286
#SPJ11
a 5100 kg open train car is rolling on frictionless rails at 25 m/s when it starts pouring rain. rain falls vertically. a few minutes later, the car's speed is 23 m/s . What mass of water has collected in the car?
111.3 kg of water have accumulated inside the car
Let us assume that the mass of water accumulated is m′. As a result, the total mass of the train-car plus the water is m + m′. The momentum of the total mass before rain = momentum of the total mass after rain. Momentum of the train before rain, p1 = mv1 Momentum of the train after rain, p2 = (m + m′) v2 .Applying the principle of conservation of momentum,p1 = p2m v1 = (m + m′) v2.
The mass of water is calculated using the above equation.
m′ = [m v1 - m v2]/v2m′ = m (v1 -v2)/v2 Substitute m = 5100 kg, v1 = 25 m/s, and v2 = 23 m/s in the above equation.
m′ = (5100 × (25 - 23))/23m′ = 111.3 kg
Therefore, the mass of water accumulated in the car is 111.3 kg.
To know more about principle of conservation of momentum click on below link :
https://brainly.com/question/30582604
#SPJ11
An unpolarized laser beam enters a container of water. The beam is partially reflected from the water-glass surface, as indicated in the figure below. For what angle of incidence will this reflected beam be completely polarized? [image attached below]
At 57.27° of angle of incidence this reflected beam will be completely polarized when initially an angle of incidence will this reflected beam be completely polarized.
The angle of incidence for which the reflected beam will be completely polarized is Brewster's angle, which is given by:
sin(θB) = n2/n1
where n1 is the refractive index of the medium that the beam is entering (in this case, water), and
n2 is the refractive index of the medium that the beam is reflecting off of (in this case, glass).
For water the refractive index n1 = 1.333 and
for glass the refractive index n2 = 1.52,
Then, sin(θB) = 1.52/1.333 = 57.27°
Therefore, the reflected beam will be completely polarized at an angle of incidence of 57.27°.
To learn more about refractive index click here https://brainly.com/question/30761100
#SPJ1
A sound wave has a frequency of 687 Hz in air and a wavelength of 0.49 m. What is the temperature of the air? Relate the speed of sound in air to temperature in units of Kelvin, but answer in units of Celsius. Assume the velocity of sound at 0◦C is 333 m/s.
Answer in units of deg C.
The temperature of the sound air is approximately 17.57°C.
Soundwave calculation.
We can use the formula for the speed of sound in air to relate it to temperature:
v = 331.5 * sqrt(T/273.15)
where v is the velocity of sound in air, T is the temperature in Kelvin, and 273.15 K is the temperature in Kelvin at 0◦C.
We know the frequency and wavelength of the sound wave in air, and we can use the formula for the speed of sound to find the velocity of sound:
v = f * λ
where f is the frequency of the sound wave λ is the wavelength.
Plugging in the given values, we get:
v = 687 Hz * 0.49 m
v = 336.63 m/s
Now we can use the formula for the speed of sound to find the temperature:
336.63 m/s = 331.5 * sqrt(T/273.15)
Solving for T, we get:
T = (336.63/331.5)^2 * 273.15
T = 290.72 K
Converting from Kelvin to Celsius, we get:
T = 290.72 - 273.15
T ≈ 17.57°C
Therefore, the temperature of the air is approximately 17.57°C.
Learn more about soundwaves below.
https://brainly.com/question/16093793
#SPJ1
which of the following has the greatest momentum? 10.0 kg mass moving at 30 m/s 3000 kg mass moving at 0.2 m/s 0.05 kg mass moving at 200 m/s 200 kg mass moving at 2 m/s
The 10.0 kg mass moving at 30 m/s has the greatest momentum since momentum is calculated as the product of mass and velocity.
What is the momentum?The mass and velocity of each object must be taken into account when calculating momentum, and the object with the highest momentum is the one with the highest product of mass and velocity.
Momentum = mass × velocity
The momentum of each object is calculated as follows:
1. 10.0 kg mass moving at 30 m/s.
Momentum = 10.0 kg × 30 m/s = 300 kg·m/s². 3000 kg mass moving at 0.2 m/s. Momentum = 3000 kg × 0.2 m/s = 600 kg·m/s³. 0.05 kg mass moving at 200 m/s. Momentum = 0.05 kg × 200 m/s = 10 kg·m/s⁴. 200 kg mass moving at 2 m/s. Momentum = 200 kg × 2 m/s = 400 kg·m/s.
Therefore, the 3000 kg mass moving at 0.2 m/s has the greatest momentum, with a value of 600 kg·m/s.
Read more about mass here:
https://brainly.com/question/19385703
#SPJ11
(a) which draws more current, a 100-w light bulb or a 75-w bulb? (b) which has the higher resistance, a 100-w light bulb or a 75-w bulb?
The final answer are resistance of a circuit is directly proportional to the power rating of the bulb. As a result, a 75-watt light bulb has a higher resistance than a 100-watt light bulb.
(a) A 100-watt light bulb draws more current than a 75-watt light bulb.
(b) A 75-watt light bulb has a higher resistance than a 100-watt light bulb. The current drawn by a circuit is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit, as per Ohm's law.
As a result, the resistance of the light bulb can be determined by measuring the current flowing through it and the voltage across it. The resistance of a circuit is defined as the ratio of the voltage applied to the circuit to the current flowing through it.
Therefore, if we look at the above question, since the power of the bulb is proportional to the product of voltage and current, we can say that a 100-watt bulb would draw more current than a 75-watt bulb. This is due to the fact that the current drawn by the bulb is proportional to the power that the bulb can handle.
However, the resistance of a circuit is directly proportional to the power rating of the bulb. As a result, a 75-watt light bulb has a higher resistance than a 100-watt light bulb.
To know more about higher resistance refer here:
https://brainly.com/question/30548811#
#SPJ11
what types of energy changes occur during each section of the cooling curve. when is kinetic energy decreasing? when is potential energy decreasing?
During each section of the cooling curve, different types of energy changes occur. Kinetic energy decreases during the solid-to-liquid and liquid-to-gas phase transitions, while potential energy decreases during the gas-to-liquid and liquid-to-solid phase transitions.
What is a cooling curve?A cooling curve is a graph of temperature versus time that depicts the cooling of a substance. The curve is divided into four distinct sections: (i) from solid to liquid, (ii) from liquid to gas, (iii) from gas to liquid, and (iv) from liquid to solid. During each section of the cooling curve, energy changes occur.
Types of energy changes that occur during each section of the cooling curve: Solid to liquid: During this phase transition, the temperature of the substance remains constant, while the potential energy increases.Liquid to gas: During this phase transition, the temperature of the substance remains constant, while the potential energy increases.
Read more about solid :
https://brainly.com/question/752663
#SPJ11
how long must a 0.70- mm -diameter aluminum wire be to have a 0.42 a current when connected to the terminals of a 1.5 v flashlight battery?
To determine the length of an aluminum wire required to carry a certain current, one must use the formula: r = (ρL) / (πr²), where r is the radius of the wire, ρ is the resistivity of the wire, and L is the length of the wire is 48.54 m.
What is the length of the wire?A 0.70 mm diameter aluminum wire has a radius of 0.35 mm or 0.00035 m. The resistivity of aluminum is 2.82 × 10⁻⁸Ωm. The formula for current is:
I = V / R
where, V is voltage, and R is resistance. We can rearrange this to:
R = V / I
Plugging in the given values of 0.42 A and 1.5 V gives R = 3.571 Ω. The resistance of a wire is given by:
R = ρL / A
where, A is the cross-sectional area of the wire, and ρ is its resistivity.
We know the resistivity of aluminum and the radius of the wire, so we can calculate the cross-sectional area of the wire:
A = πr² = 3.1416 × (0.00035 m)² = 3.848 x 10⁻⁷ m². Substituting all the values in the formula for the resistance of the wire and solving for L gives:
L = RA / ρ = (3.571 Ω) × (3.848 x 10⁻⁷ m²) / (2.82 × 10⁻⁸ Ωm) = 48.54 m.
Therefore, the aluminum wire must be 48.54 m long to have a current of 0.42 A when connected to the terminals of a 1.5 V flashlight battery.
Read more about length here:
https://brainly.com/question/28322552
#SPJ11
the intensity of sound in a typical classroom is approxiamtely 10^-7 w/m2. what is the sound level for this noise/
The sound level for this noise is approximately 50 decibels.
Sound level is a logarithmic measure of the ratio between the sound pressure level of a particular sound wave and a reference level. The reference level is typically set at the threshold of human hearing, which corresponds to an intensity of 10^-12 W/m^2. The sound level (measured in decibels, dB) of a sound wave is given by,
L = 10 log10(I/I0)
where I is the intensity of the sound wave and I0 is the reference intensity, which is typically set at 10^-12 W/m^2.
So, for an intensity of 10^-7 W/m^2 in a typical classroom, we can calculate the sound level as,
L = 10 log10(I/I0) = 10 log10(10^-7/10^-12) = 10 log10(10^5) = 50 dB
To know more about sound, here
brainly.com/question/30546291
#SPJ4
an n-type piece of silicon experiences an electric field equal to 0.1v/m. (a) calculate the velocity of electrons and holes in this material
In an n-type piece of silicon, the electric field causes the electrons to accelerate due to the attractive force between the negatively charged electrons and the positively charged electric field. This acceleration causes the electrons to reach a velocity of V = E/μ, where E is the electric field (0.1V/m) and μ is the mobility of electrons in silicon (1350 cm2/V⋅s). Therefore, the velocity of electrons in this material would be equal to 0.1V/m/1350cm2/V⋅s = 0.0741 cm/s.
The holes, on the other hand, experience a repulsive force due to the positive electric field. This causes the holes to decelerate, with a velocity of V = -E/μ. Therefore, the velocity of holes in this material would be equal to -0.1V/m/1350cm2/V⋅s = -0.0741 cm/s.
Know more about electric field here:
https://brainly.com/question/8971780
#SPJ11
in which of the following situations do the forces on the body sum to zero? vertical forces of -80 n, 30 n, and 40 n horizontal forces of -50 n, -20 n, 40 n, and 30 n neither a nor b both a and b need more information to calculate
The situation in which the forces on the body sum to zero is option b, horizontal forces of -50 n, -20 n, 40 n, and 30 n.
When the net force acting on an object is zero, the forces on the body sum to zero. This is known as the equilibrium state. The body is said to be in equilibrium when the net force on it is zero. An object can be in equilibrium when there is no acceleration in the system.
Let's determine which option from the given options meets this criteria:
Vertical forces of -80 N, 30 N, and 40 N
The net force acting on the object would be:
30 + 40 - 80 = -10 N.
In this case, the forces do not sum to zero. Therefore, it is not in its equilibrium state.
Horizontal forces of -50 N, -20 N, 40 N, and 30 N
The net force acting on the object would be:
-50 -20 + 40 + 30 = 0 N.
In this case, the forces sum to zero. Therefore, the body is in equilibrium state.
So, the answer is option b.
Learn more about equilibrium state here: https://brainly.com/question/517289.
#SPJ11
if the club and ball are in contact for 1.80 ms , what is the magnitude of the average force acting on the ball?
The average force acting on the golf ball is 0.637 N.
To calculate the average force acting on the golf ball, we will use the equation
F = m*a
where F is the average force, m is the mass of the golf ball, and a is the acceleration.
To calculate the acceleration, we can use the equation
a = (vf - vi)/t
where vf is the final velocity, vi is the initial velocity (0 m/s in this case), and t is the time of contact. We know that the final velocity is 25.0 m/s, and the time of contact is 1.80 ms.
Therefore, we can calculate the acceleration to be
a = (25.0 m/s - 0 m/s) / 1.80 ms
a = 13.89 m/s².
Now that we have the mass and acceleration, we can calculate the average force. Using the equation F = m*a, the average force on the golf ball is
F = 0.0450 kg * 13.89 m/s² = 0.637 N.
Learn more about force acting at https://brainly.com/question/29268524
#SPJ11
A hairdryer has a power of 1.5 KW and was used for 15 minutes how much did it cost?
(a) calculate the (time-averaged) energy density of an electromagnetic plane wave in a conducting medium. show that the magnetic contribution always dominates (b) show that the intensity is (k/2uw)e0^2
(a)The time-averaged energy density is:U = (1/2μ) |E x B|² = (1/2μ) E₀² B₀² sin²(kx - ωt).
(b)The intensity of an electromagnetic wave is defined as the time-averaged power per unit area. It can be calculated using the Poynting vector: I = <S> = (1/2μ) |E x B|².
S = (1/μ) E x B
where E is the electric field, B is the magnetic field, and μ is the permeability of the medium. In a conducting medium, the permeability is generally the same as that of free space, so μ = μ0.
The time-averaged energy density is then given by:
U = (1/2μ) |E x B|^2
where |E x B| is the magnitude of the cross product of the electric and magnetic fields. Since the cross product of two vectors is orthogonal to both vectors, |E x B| represents the strength of the electromagnetic field.
In a plane wave, the electric and magnetic fields are perpendicular to each other and to the direction of propagation. Without loss of generality, let's assume that the electric field is in the x-direction and the magnetic field is in the y-direction. Then we have:
E = E₀ sin(kx - ωt) i
B = B₀ sin(kx - ωt + π/2) j
where E₀ and B₀ are the amplitudes of the fields, k is the wave vector, ω is the angular frequency, and i and j are unit vectors in the x- and y-directions, respectively.
Taking the cross product of E and B, we have:
E x B = E₀ B₀ sin(kx - ωt) k
Therefore, the time-averaged energy density is:
U = (1/2μ) |E x B|² = (1/2μ) E₀² B₀² sin²(kx - ωt)
Since the sine function oscillates between -1 and 1, the maximum value of sin^2(kx - ωt) is 1. Therefore, the maximum value of the energy density is:
Umax = (1/2μ) E₀² B₀²
Note that the energy density is proportional to both the electric and magnetic field strengths. However, the permeability of a conducting medium is generally less than that of free space, which means that the magnetic field is amplified relative to the electric field. This leads to a situation where the magnetic contribution to the energy density dominates over the electric contribution.
(b) The intensity of an electromagnetic wave is defined as the time-averaged power per unit area. It can be calculated using the Poynting vector:
I = <S> = (1/2μ) |E x B|²
where the brackets denote a time average.
The energy density U is related to the intensity I by:
U = I/ω
where ω is the angular frequency. Substituting the expression for U from part (a), we have:
I/ω = (1/2μ) E₀² B₀²
Solving for I, we obtain:
I = (ω/2μ) E₀² B₀²
Recall that the speed of light in a medium is given by:
v = 1/√(με)
where ε is the permittivity of the medium. Therefore, the wave number k and the angular frequency ω are related by:
k = ω/v = ω√(με)
Substituting this expression into the expression for I, we have:
I = (k/2uw) E₀²
Click the below link, to learn more about electromagnetic plane wave :
https://brainly.com/question/29763072
#SPJ11