At separation of 1470 meters, the two charges exert a force of 0.70 N on each other.
What is electric force?Electric force is the interaction between any two charged objects that can be either attractive or repelling. Newton's rules of motion, which apply to all forces, explain how each one affects the target body and how it does so. The electric force is one of the many forces that operate on objects.
We know that electric force can be mathematically defined as:
F = kQq/r²
0.70 = 9.0 × 10⁹ × (6.0×10⁻⁹)²/r²
r = 1.47 meter.
Hence, the separation between two charges is 1.47 meters.
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19. A pitcher throws a baseball toward a batter at 30m/s. The batter swings his
bat and hits the baseball. The baseball flies away in the opposite direction at a
speed of 35m/s. Is there a transfer of energy in this situation? (SC.7.P.11.4)
a) Yes, because both the bat and the ball are moving after the collision.
b) No, because the ball and the bat only touched for a short time.
c) Yes, because the force from the bat changes the motion of the ball
A pitcher throws a baseball towards a batter at 30m/s. The batter swings his bat and hits the baseball, then there is a transfer of energy in this situation : c) Yes, because the force from the bat changes the motion of the ball.
How is energy transferred from baseball bat to a baseball?Although baseball may appear hard and solid, it actually behaves much like a rubber ball. In the fraction of a second that ball collides with the swinging bat, ball compresses as the energy of motion goes into deforming the ball and transforms it into an elastic potential energy.
The collision of baseball with bat is elastic and the collision between baseball and glove is nearly inelastic.
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Chromatic aberration occurs when:___.
a. a mirror does not focus all colors of light to the same place.
b. a lens does not focus all colors of light to the same place.
c. the absorption of blue light by an intervening dust cloud causes a star to look redder than it really is.
d. atmospheric scattering causes the Sun to look red at sunset.
Answer:
b. a lens does not focus all colors of light to the same place.
Explanation:
Chromatic aberration is a defect of a lens. In this defect, the lens is unable to focus the different wavelengths of the light on a single focal point. It is also known as chromatic distortion and color fringing. It is caused by the dispersion of light while passing through a lens. As a result, the image might become blurred and different colors are observed around its edges. It can be corrected by the use of a combination of converging and diverging lenses.
Hence, the correct option will be:
b. a lens does not focus all colors of light to the same place.
An ice-making machine inside a refrigerator operates in a Carnot cycle. It takes heat from liquid water at 0.0 degrees Celsius and rejects heat to a room at a temperature of 20.6 degrees Celsius. Suppose that liquid water with a mass of 82.1 kg at 0.0 degrees Celsius is converted to ice at the same temperature. Take the heat of fusion for water to be Lf=3.34×105 J/kg.
A. How much heat |QH| is rejected to the room?
B. How much energy E must be supplied to the device?
Answer:
A. Q = 2.74 x 10⁷ J = 27.4 MJ
B. E = 3.91 x 10⁸ J = 391 MJ
Explanation:
A.
Heat rejected can be found as follows:
[tex]Q = mL[/tex]
where,
Q = Heat rejected = ?
m = mass = 82.1 kg
L = Latent Heat of fusion = 334000 J/kg
Therefore,
[tex]Q = (82.1\ kg)(334000\ J/kg)[/tex]
Q = 2.74 x 10⁷ J = 27.4 MJ
B.
First, we will calculate the efficiency of the Carnot Cycle as follows:
[tex]Efficiency = 1-\frac{T_1}{T_2}[/tex]
where,
T₁ = Heat intake temperature = 0°C + 273 = 273 k
T₂ = Heat rejection temperature = 20.6°C + 273 = 293.6 k
Therefore,
[tex]Efficiency = 1 - \frac{273\ k}{293.6\ k} \\\\Effciency = 0.07[/tex]
Therefore, the energy input required is:
[tex]Efficiency = \frac{Q}{E}\\\\E = \frac{Q}{Efficiency} = \frac{2.74\ x\ 10^7\ J}{0.07}[/tex]
E = 3.91 x 10⁸ J = 391 MJ
Which one of the following statements about velocity is true?
O Velocity is the magnitude of speed.
O Velocity is the displacement of an object divided by the time interval.
O Velocity describes how fast an object is changing speed.
O Speed and velocity refer to the same vector quantity.
Answer:
Velocity is the displacement of an object divided by the time interval.
Explanation:
Let's consider each choices:
1. Velocity is not the magnitude of speed. Velocity is a vector quantity which means it consists of both direction and magnitude. Speed is the magnitude of velocity, not the other way around.
3. Velocity describes how fast an object is changing speed. If a speed changes each time interval, that is not a velocity but rather the magnitude of acceleration. Magnitude of acceleration is change in speed over time. Acceleration is the one that describes how velocity is changing through time.
4. Speed and velocity refer to the same vector quantity. Speed is not a vector quantity but a scalar quantity which only has magnitude. Speed is also considered as the magnitude of velocity as well.
Therefore, the only correct choice is 2. Velocity is the displacement of an object divided by the time interval. This is true since velocity is change in position (displacement) over time.
draw diagram of how a reflecting telescope works. show how the angles of reflection would work with mirrors placed at 2 different angles
Lenses, which are pieces of curved, clear glass, were employed in early telescopes to focus light.
What is Telescope?Curved mirrors are used by the majority of telescopes nowadays to collect light from the night sky. Light is focused by a telescope's mirror or lens' shape.
Astronomers use a telescope to observe distant things. Curved mirrors are used by the majority of telescopes, including all large telescopes, to collect and concentrate light from the night sky.
The original telescopes employed lenses, which are simply curved pieces of clear glass, to focus light. The "optics" of a telescope are the mirrors or lenses. Strong telescopes may view objects that are extremely faint and incredibly far away.
Therefore, Lenses, which are pieces of curved, clear glass, were employed in early telescopes to focus light.
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A flashlight can be made that is powered by the induced current from a magnet moving through a coil of wire. The coil and magnet are inside a plastic tube that can be shaken causing the magnet to move back and forth through the coil. Assume the magnet has a maximum field strength of 0.05 T. Assume that the radius of the coil is 1.5 cm and the magnet is shaken with a frequency of about two shakes per second. Specify the the number of turns necessary to light a standard 1-watt, 3-V flashlight bulb.
Answer:
n = 4.25 x 10⁴ .
Explanation:
EMF required to be produced = 3 V .
Let n be the required no of turns .
rate of change of flux = n x B x A x f where n is no of turns of coil , B is magnetic field , A is area of coil and f is frequency of change .
B = .05 T , A = π x (.015)² = 7.065 x 10⁻⁴ m² , f = 2
emf induced = rate of change of flux
= n x .05 T x 7.065 x 10⁻⁴ m² x 2
= .7065 x 10⁴ x n
Given
.7065 x 10⁻⁴ x n = 3
n = 4.25 x 10⁴ .
Until 1979, the world's easiest driving test was administered in Egypt. To pass the test, one needed only to drive about 6 m forward, stop, and drive the same distance in reverse. Suppose that at the end of the 6 m the car's brakes are suddenly applied and the car slides to a stop. If the force required to stop the car is 6.0 X 10^3 N and the coefficient of kinetic friction between the tires and pavement is 0.77, what is the magnitude of the car's normal force? What's the car's mass?
(a) The magnitude of the car's normal force is 7,792.2 N.
(b) The mass of the car is 795.1 kg.
What is the weight of the car?
The weight of the car is calculated by applying Newton's second law of motion as shown below.
Mathematically, the formula for Newton's second law of motion is given as;
Ff = μW
where;
W is the weight of the carμ is the coefficient of kinetic friction between the tires and pavementThe weight of the car is calculated as follows;
W = Ff / μ
W = ( 6,000 N ) / ( 0.77 )
W = 7,792.2 N
Based on Newton's third law of motion, the weight of the car acting downwards is equal to normal force on the car, acting upward.
The mass of the car is calculated as follows;
W = mg
where;
m is the mass of the carg is acceleration due to gravitym = W / g
m = ( 7792.2 ) / (9.8)
m = 795.1 kg
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Can you help me with this question
A bar magnet's magnetic field lines flow from its north pole toward its south pole, just like they do in all magnets. Field lines that begin close to a pole's edges stay nearby the bar magnet longer than those that begin closer to the pole's centre.
What produces a magnetic field in a bar magnet?Because the molecules in magnets are arranged so that their electrons spin in the same direction, magnets are unique. This configuration and motion produces a magnetic force that emanates from a north- and south-seeking pole, respectively.
Where does a bar magnet's magnetic field are strongest?At the poles, it is strongest.
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Describe the role of the teacher and the learner in a natural science and technology classroom
Students are instructed in subject-specific classes by science professors. They develop lesson plans, assess student performance, and educate using lectures, technology.
What are the characteristics of a good teacher?The teacher who gives their best in order to develop the skills in all student of their class. A good teacher has to be a great command of his/her subjects.
He/she has to put their effort to improve the weak student of the class as well must appreciate the effort of good students.
The role of the teacher and the learner in a natural science and technology classroom is;
Students are instructed in subject-specific classes by science professors. They develop lesson plans, assess student performance, and educate using lectures, technology,
They also serve as role models for anticipated conduct in order to develop and maintain an ordered, disciplined classroom.
They must also be analytical since they must analyze kids' development and modify lesson plans for special-needs children.
They may create and sustain interpersonal ties with students, parents, other staff members, and administrators.
Hence the role teacher is to instruct the student, maintain discipline and educate using technology.
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Which of the following are characteristics of noble gases?
A. They're highly reactive elements.
B. They're inert
C. They're found in Group 1.
D. They don't react with other elements.
Which of the following are characteristics of noble gases?
[tex]{ \bf{ \underbrace{Answer :}}}[/tex]
[tex]\sf\red{B. \:They're\: inert.}[/tex] ✅
An inert gas is one that does not undergo chemical reactions. The noble gases have complete outer shells, so they have no tendency to lose, gain, or share electrons. This is why they are said to be inert.[tex]\sf\purple{D.\: They \:don't \:react\: with\: other\: elements.}[/tex]✅
Noble gases are the least reactive of all elements. This is because they already have the desired eight total 's' and 'p' electrons in their outermost (highest) energy level.[tex]\circ \: \: { \underline{ \boxed{ \sf{ \color{green}{Happy\:learning.}}}}}∘[/tex]
What causes the poles of the electromagnet in an audio speaker to repeatedly switch directions?
a metal striker that pulls on the magnet
a diaphragm that vibrates around the magnet
a current that rapidly switches direction
a device that opens and closes a circuit
Answer:
he is right its c
Explanation:
Answer:
a current that rapidly switches direction
Explanation:
2. How much work is done in lifting 214kg from the floor to a shelf at a height of 6m?
Answer:
12583.2 J or 12.5832 KJ
Explanation:
Work done can be expressed as force multiplied by displacement, or
W = Fs
In this case, we can calculate the force by using F = mg.
m is the mass, 214 kg, and g is gravitational acceleration, which is 9.8 m/s/s.
So, we Calculate 214 * 9.8 to get 2097.2
The displacement is 6m.
So, by doing W = Fs, we get
2097.2 * 6 = 12583.2 Joules
A 42 kg cart is pushed forward with a total force of 225 Newtons. What is the work done if the cart moves forward 12 meters
Important Formulas:
[tex]w=Fd[/tex]
work(measured in joules) = force(measured in newtons) * distance(measured in meters)
__________________________________________________________
Given:
[tex]m=42kg[/tex]
[tex]F=225N[/tex]
[tex]d=12m[/tex]
[tex]w=Fd[/tex]
__________________________________________________________
Finding work:
[tex]w=Fd[/tex]
[tex]w=225\times12[/tex]
__________________________________________________________
[tex]\fbox{w = 2700 Joules}[/tex]
PLEASE HELP ME URGENT
Here's the solution,
A.) calculate work done :
we know,
[tex]weight \: = mass \times acceleration[/tex]
[tex]weight = 10 \times 10[/tex][tex]weight = 100 \: Newtons[/tex]And,
[tex]work \: done = force \times dispacement[/tex]
[tex]work \: done = 100 \: \times \: 20[/tex][tex]work \: done = 2000 \: joules[/tex]B.) find power :
[tex]power = \dfrac{work \: done}{time} [/tex]
[tex] power = \dfrac{2000}{2} [/tex][tex]power = 1000 \: watt[/tex]Answer:
work done=2000J and power=1000w
Explanation:
(a) Work done= Gravitational potential energy
W=mgh
Data,
m=10kg
h=20m
g=10N/kg
W=10kg*10N/kg*20m
W=2000J or 2kJ
(b). power=work done/time
P=2000/2
P=1000w
Write two or three sentences to describe the conductivity of a conductor. Explain its conductivity in terms of the electrons in it.
The conductivity of a conductor refers to its ability to conduct electrical current.
A material that has high conductivity allows electrical charges to flow through it easily and with little resistance, while a material with low conductivity does not allow electrical charges to flow as easily and has more resistance.
The conductivity of a conductor is determined by the number of free electrons in the material, as well as how easily these electrons can move through the material.
In a conductor, the atoms are closely packed together and the electrons are not tightly bound to the atoms, allowing them to move freely through the material and carry an electrical charge. This facilitates the flow of electrical current through the material, resulting in high conductivity.
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The weight of an object changed if the force of gravity changes? True or false
Answer:
True. If you bring a bowling ball away from earth it would weigh less because the less gravity pushing down on it.
Answer:
f
Explanation:
If a runner has a speed of 8.66m/s and runs for 46.2s what distance is covered? tv = d
v=
d=
t=
Answer:
[tex]\text{Using the formula: }v=\frac{d}{t}\\\therefore vt=d\\\text{Plug and chug:}46.2(8.66)=400.092\text{ metres}[/tex]
An astronaut has two springs: Spring A and Spring B. She also has two metal blocks that she can hang from the springs: Block X and Block Y. At her lab in Orlando, Florida, she hangs Block X from Spring A and sees that Spring A stretches 2.04 cm as a result. Later, at a research station on the moon, she hangs block X from spring A and finds that Spring A only stretches 0.34 cm. Then (still on the moon) she hangs block Y from Spring A and sees that spring A stretches 0.54 cm.
1) How much would spring A stretch if Block Y were hanging from it back in the lab in Orlando?
2) On the moon, when Block Y is hanging from Spring B, Spring B stretches a distance of 1.3 cm. In Orlando, how much would Spring B stretch when Block X is hanging from it?
Answer:
Explanation:
Let the spring constant of spring A and B be k₁ and k₂ . Mass of box X and Y be m₁ and m₂ .
Force created in spring which is stretched by d is kd where k is spring constant .
At her lab in Orlando, Florida,
k₁ x .0204 m = m₁ g where g is acceleration due to earth's gravity
k₁ = 49 m₁ g
At a research station on the moon
k₁ x .34 x 10⁻² m = m₁ g₁ where g₁ is acceleration due to gravity at moon
k₁ = 294 .11 m₁ g₁
49 m₁ g = 294 .11 m₁ g₁
g = 6.0022 g₁
At a research station on the moon
k₁ x .54 x 10⁻² m = m₂ g₁
k₁ = 185.18 m₂ g₁
294 .11 m₁ g₁ = 185.18 m₂ g₁
1.588 m₁ = m₂
1 )
At her lab in Orlando, Florida,
k₁ x d = m₂ g , where d is the new stretch that is to be calculated .
185.18 m₂ g₁ d =m₂ g
185.18 d g₁ = g
185.18 d g₁ = 6.0022 g₁
d = .03241 m
= 3.24 cm .
2 )
At a research station on the moon
when Block Y is hanging from Spring B
k₂ x .013 = m₂ g₁
k₂ = 76.92 m₂ g₁
At her lab in Orlando, Florida,
Spring B stretch when Block X is hanging from it
k₂ d₁ = m₁ g
76.92 m₂ g₁ d₁ = m₁ g
76.92 m₂ g₁ d₁ = m₁ 6.0022 g₁
76.92 m₂ d₁ = m₁ 6.0022
12.815 x 1.588 m₁ x d₁ = m₁
d₁ = .049 m
= 4.9 cm .
In this exercise we have to use the knowledge of springs to calculate the distance from it, that way:
A)d=3.24 cm
B)d=4.9 cm
So, before starting the calculations, we have to organize the values and put everything in function of a single unknown such as:
[tex]k_1 * 0.34 * 10^{-2} m = m_1 g_1\\ k_1 = 294 .11 m_1 g_1\\49 m_1 g = 294 .11 m_1 g_1\\g = 6.0022 g_1\\k_1 *0 .54 * 10^{-2} m = m_2 g_1\\k_1 = 185.18 m_2 g_1\\294 .11 m_1 g_1 = 185.18 m_2 g_1\\1.588 m_1 = m_2[/tex]
A) By calculating the distance we find that:
[tex]k1_1 * d = m_2 g\\185.18 m_2 g_1 d =m_2 g\\185.18 d g_1 = g\\185.18 d g_1 = 6.0022 g_1\\d = 0.03241 m= 3.24 cm[/tex]
B) So now calculating the distance from the lab to the moon, so:
[tex]k_2* 0.013 = m_2 g_1\\k_2 = 76.92 m_2 g_1\\k_2 d_1 = m_1 g\\76.92 m_2 g_1 d_1 = m_1 g\\76.92 m_2 g_1 d_1 = m_16.0022 g_1\\76.92 m_2 d_1 = m_1 6.0022\\12.815 * 1.588 m_1 * d_1= m_1\\d_1 = 0.049 m = 4.9 cm[/tex]
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An astronaut weights 8x10^2
Answer:
800
Explanation:
10^2 = 100
8 x 100 = 800
Cart A with a mass of 28kg is moving to the RIGHT at 11m/s and Cart B with a mass of 17kg is moving LEFT at negative 9m/s. The carts collide and STICK TOGETHER. What is the velocity of the carts after they collide?
Answer:
Should be 17.8m/s
Explanation:
Initial momentum = Final momentum
(m1×v1)+(m2×v2)=(m1+m2)v since its an inelastic collision.
5. If a jump rope is shaken fast enough to produce a wave with a wavelength of 0.5 m and
the crest of the wave passes a specific point 6 times per second, what is the velocity of the
wave?
Answer:
After solving the equation the wave is traveling at a velocity of 3 m/s.
What is velocity?Velocity is a vector quantity that describes the rate at which an object changes its position. It is a measure of both the speed and the direction of an object. Velocity is typically expressed in terms of meters per second (m/s). When an object is in uniform motion, its velocity is constant, meaning that it is not changing in magnitude or direction. If an object is accelerating, its velocity is changing over time, either in magnitude, direction, or both.
The velocity of the wave can be calculated using the following equation:
Velocity = Wavelength x Frequency
In this case, the wavelength is 0.5 m and the frequency is 6 Hz (6 cycles per second). So, the velocity of the wave is:
Velocity = 0.5 m x 6 Hz = 3 m/s
This means that the wave is traveling at a velocity of 3 m/s.
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A student pours a spoonful of dirt into a cup of water. The water and dirt are stirred together. The water turns a light brown color. Some dark pieces float to the top of the cup and another dark layer forms on the bottom of the cup. Which statement BEST describes the contents of the cup?
The statement that is correct is that the contents of the cup form a mixture.
What is the nature of the cup?Though the question is incomplete but I would try to give you a good explanation as much as I can. We must recall that when we talk about a mixture, we have to note that the term mixture would refer to the combination of two or more substances that do not chemically react together.
In this case, we have been told that we have a water that was pure and then we add dirt to it. It is clear that the water and the dirt do not react in any way hence what we have formed is a mixture.
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A 2.0-kg laptop sits on the horizontal surface of the seat of a car moving at 8.0 m/s. The driver starts slowing down to stop. Find the minimum stopping distance so the computer does not slip and fall onto the floor if the coefficient of static friction between the seat and the laptop is 0.40 and the coefficient of kinetic friction is 0.20.
Answer: [tex]32.65\ m[/tex]
Explanation:
Given
mass of laptop m=2 kg
The velocity of car u=8 m/s
The coefficient of static friction is [tex]\mu_s=0.4[/tex]
The coefficient of kinetic friction is [tex]\mu_k=0.2[/tex]
As the car is moving, so the coefficient of kinetic friction comes into play
deceleration offered by friction [tex]\mu_kg=0.2\times 9.8\ m/s^2[/tex]
Using the equation of motion [tex]v^2-u^2=2as\\[/tex]
insert the values
[tex]0^2-8^2=2(-0.2\times 9.8)s\\\\s=\dfrac{64}{1.96}\\\\s=32.65\ m[/tex]
the work a force does is measured in?
Explanation:
work a force is measured in newton-meters (N-m)
[tex] \huge \hookrightarrow \mathfrak{ \green{Answer}}[/tex]
we know,
[tex] \boxed{ \small{workdone = force \times displacement}}[/tex]
[tex]\longmapsto \: work \: done = N \times m[/tex]
[tex]work \: \: done \: \: is \: \: measured \: \: in \: \: \boxed {\color{gold}{Nm}}[/tex]
Nm = Newton meter
Which of the following could be used as an INSULATOR?
a.) plastic plate
b.) silver spoon
c.) copper wire
d.) gold necklace
Answer:
Probably copper wire
Explanation:
I took the class and that's the only one that sounds right but I'm pretty dum lol
Drag and drop the terms at the left to match the appropriate descriptions at the right. ResetHelp Visual acuity Emmetropia Accommodation Astigmatism Myopia Hyperopia Presbyopia Refraction : normal vision. : reduction in visual acuity due to irregularities in the cornea or lens. : farsightedness. : nearsightedness. : age-related farsightedness due to loss of elasticity in the lens. : sharpness of vision. : bending of light rays. : changes the shape of the eye lens to focus light on the retina.
Answer: Visual acuity: sharpness of vision.
Myopia: nearsightedness
Refraction: bending of light rays.
Emmetropia: normal vision.
Accommodation: changes the shape of the eye lens to focus light on the retina.
Presbyopia: age-related farsightedness due to loss of elasticity in the lens.
Astigmatism: reduction in visual acuity due to changes in the cornea or lens.
Hyperopia: farsightedness
Myopia and hyperopia are refractive errors of the eye.
Presbyopia occurs in old age people.
Explanation:
Visual acuity: It can be defined as the inability to observe the details of shape of the object. Person loses sharpness in vision.
Myopia: It is a defect in vision in which person is able to observe the near by objects clearly but not able to see the distant objects.
Refraction: It can be defined as the bending of beam of light when it passes through from one substance to another.
Emmetropia: It is a vision without any defect.
Accommodation: It is the ability of the eye to adjust its focal length and adjusting the light on focus.
Presbyopia: It can be defined as the loss of ability of eye to focus on the object. It occurs in old age.
Astigmatism: It is a refractive error in which the eye does not focus light on retina.
Hyperopia: It is also called as farsightedness. Distant objects can be seen clearly but nearby appears blurry.
Calculate the potential energy of a rock of mass 500 g, held at a height of 2 m above ground.
The potential energy of a rock of mass 500 g, held at a height of 2 m above ground is 9.8J.
The formula for the gravitational potential energy of an object is:
PE = mgh
where m is the mass of the object, g is the acceleration due to gravity (approximately 9.8 m/s^2 on the Earth's surface), and h is the height of the object above the reference point.
So, in this case, we can plug in the given values to find the potential energy of the rock:
PE = (500 g) x (9.8 m/s^2) x (2 m)
The weight of the rock is m*g = 500 g * 9.8 m/s^2 = 4.9 N
Therefore,
PE = 4.9 N x 2 m = 9.8 J
Therefore, the potential energy of a rock of mass 500 g, held at a height of 2 m above ground is 9.8J.
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1. At a location in Europe, it is necessary to supply 1000 kW of 60-Hz power. Only power sources available operate at 50 Hz. It is decided to generate the power by means of a motor-generator set consisting of a 20- pole synchronous motor (its electrical rotating frequency is 50 Hz) driving a synchronous generator. How many poles should the synchronous generator have in order to convert 50-Hz power to 60-Hz power
Answer:
Explanation:
From the given information:
The speed of a synchronous motor in relation to its frequency can be represented with the formula:
[tex]n_{sm}= \dfrac{120f_{se}}{P}[/tex]
where,
the electrical frequency [tex]f_{se}[/tex] is measured in Hz
the number of poles = P
For us to estimate the number of poles to have 50 Hz - 60 Hz Power, then we need to relate the frequencies of the above equation.
i.e
[tex]\dfrac{120(50 \ Hz)}{P_1}= \dfrac{120( 60 \Hz)}{P_2} \\ \\ \dfrac{6000 \ Hz}{P_1}= \dfrac{7200 \ Hz}{P_2} \\ \\ \dfrac{P_2}{P_1}=\dfrac{7200}{6000} \\ \\ \\ \dfrac{P_2}{P_1}= \dfrac{12}{10}[/tex]
Thus, we can conclude that 10 poles synchronous motor is attached with 12 poles synchronous generator in order to convert 50 Hz to 60 Hz power.
Sarita Has power of 480 watt. Calculate the amount of mass lifted by her up to 10 Metres in 12 SECONDS?
Answer:
58.7g (answer might differ a little if the answer treats g as 10 instead of 9.81ms-2)
Explanation:
First, apply the formula Energy = Power x Time
Power -> 480W (given)
Time -> 12 seconds (given)
Hence,
Energy = (480 x 12) J (SI units of energy is in Joules, J)
= 5760 J
Since Sarita lifts up the mass, the energy we have calculated above is gravitational potential energy.
That means 5760 J of gravitational potential energy.
Recall that another formula for gravitational potential energy (GPE) is
GPE = mgh (where h is the height lifted, mass is the mass and g is the gravitational constant of 9.81ms-2)
h = 10 metres (given)
Therefore,
5760 = m x 9.81 x 10
98.1m = 5760
m = 58.71559g
Hence, mass lifted is 58.7g (in 3sf)
which of the following changes will increase the period of an oscillating spring mass system?
a. an increase in the mass on the spring.
b. an increase in the initial displacement of the spring.
c. an increase in the spring constant.
d. more than one of the above.
e. none of the above.
explain your answer. NO LINKS.
Answer:
a. an increase in the mass on the spring.
Explanation:
An increase in the mass on the spring will increase the period of an oscillating spring mass system.
Mathematically, the period of an oscillating spring mass system is given by the formula;
T = 2π √(m/k)
Where;
T is the period.
m is the mass of the spring.
k is the spring constant.
Hence, the mass of a spring is directly proportional to the period of oscillation of the spring.
This ultimately implies that, as the mass of the spring increases, the period of oscillation will increase. Similarly, the period of oscillation will decrease with an increase in the spring constant.