a) density = 93.6g/12cm³
= 7.8g/cm³
b) The reason is alloying
Explanation:
volume of the rectangular block = l× b × h
= (4 × 2 × 1.5)cm
= 12 cm³
density = mass/ volume
mass = 93.6g
volume = 12cm³
therefore,
density = 93.6g/12cm³
= 7.8g/cm³
b) °Steel is formed when alloying Iron with carbon.
°Alloying improves the physical properties of the metals and non-metals
The elevators in the Landmark Tower in Yokohama, Japan are among the fastest in the world. After starting from rest, they reach a maximum speed of 120 meters per minute. It takes the elevator 4.0 seconds to reach maximum speed. What is its acceleration in m/s/s (meters per second per second)?
Answer:
The acceleration is 30 m/s²
Explanation:
Given that,
Maximum speed = 120 m/s
Time = 4.0 sec
We need to calculate the acceleration
Using equation of motion
[tex]v=u+at[/tex]
Where, v = speed
u = initial speed
a = acceleration
t = time
Put the value into the formula
[tex]120=0+a\times4.0[/tex]
[tex]a=\dfrac{120}{4.0}[/tex]
[tex]a=30\ m/s^2[/tex]
Hence, The acceleration is 30 m/s²
Exercise Book: 18
A piece of
radioactive material contains
2000 atoms. If its half life is 20 seconds
the time take for 125 atoms to remain is?
Which of the following is a unit of volume in the English system of measurement? (4 points)
Meters
Gallons
Liters per cubic gram
Kilograms per cubic centimeter
Answer:
Explanation:
the answer is gallons because i got it right on the exam
what does it mean standard unit?
Answer:
Standard unit is a standard measure that remains the same whenever, wherever and by whoever it is used. eg: The standard unit of time is second.in a series circuit, why is the current always the same?
Answer:
here lol
Explanation:
look at the photo thank you
Answer: The ballon could get rub on a carpet to gain electricity and it would have enoght force
Explanation:
25. Describe how the atomic mass unit (amu) was derived and how the mass of the electron relates to the
mass of the nuclear particle.
HELP ASAP
Answer:
ok
Explanation:
why light waves are called electromagnetic waves ?
where are some places that cyber bullying occurs? Check all that apply
A in classrooms
B in text messages
C on playgrounds
D on websites
E on social media networks
F in chat rooms.
help im being timed 01:51:15
Answer:
B, E, F
Explanation:
Because cyberbullying happens online, text messages, social media networks, and chat rooms can all have cyberbullying, because they are all ways to chat online. D does not apply, because on most websites there are not ways to chat.
Answer:
B D E AND F
Explanation:
What happens to the velocity of a sound wave in air if the temperature of the air increases?
A.
velocity increases
B. velocity does not change
c. velocity decreases
D. velocity drops to zero
How much kinetic energy does a baseball with a mass of 0.143 kg have it it is traveling at a velocity of 41.1 m/s?
89.7 Joules
108 3 Joules
156.6 Joules
120.8 Joules
Answer:
E = 120.77 J
Explanation:
Given that,
Mass of a baseball, m = 0.143 kg
Velocity of a baseball, v = 41.1 m/s
We need to find the kinetic energy of the baseball. We know that the kinetic energy of an object is associated with its motion. It can be given by the formula as follow :
[tex]E=\dfrac{1}{2}mv^2\\\\E=\dfrac{1}{2}\times 0.143\ kg\times (41.1\ m/s)^2\\E=120.77\ J[/tex]
So, the kinetic energy of the baseball is 120.77 J.
The kinetic energy of the baseball is 120.8 J.
What is kinetic energy?The kinetic energy of an object is associated with its motion. It can be related to the mass and velocity as
K.E = 1/2 mv²
Given is the Mass of a baseball, m = 0.143 kg and Velocity of a baseball, v = 41.1 m/s
substitute the values, we have
K.E = 1/2 x 0.143 x (41.1)²
K.E = 120.77 J
Hence, the kinetic energy of the baseball is 120.8 J.
Learn more about kinetic energy.
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True or False : the collect of evidence fall onto the detectives that arrive at a crime scene
Answer:true
Explanation:
List three examples of familiar organisms known as plants as used in the cell
Answer:
rose
sunflower
seaweed
15. What change of state occurs when butter turns into a liquid in a hot pan?
Answer:
Physical change from solid to liquid where it is a reversible reaction as melted butter can be frozen to its original form
Atoms are known to form charges due to their ability to gain and lose electrons in reactions. As a result, atoms
become ions that are positively or negatively charged depending on the loss or gain of electrons. Which of the
following atoms has a charge of +2 given the number of electrons?
O A. O: 10 electrons
OB. N: 10 electrons
O C. Fe: 24 electrons
OD. Cl: 18 electrons
Answer:
C. Fe: 24 electrons
Explanation:
From the analogy given, the atom with a charge of +2 is Fe having 24 electrons.
To calculate the charges on an atom;
Number of charges = Number of protons - Number of electrons.
O: 10 electrons: 8 protons = 8 - 10 = -2
N: 10 electrons; 7 protons = 7 - 10 = -3
Cl: 18 electrons; 17 protons = 17 - 18 = -1
So;
Fe: 24 electrons and 26 protons = 26 -24 = +2
Therefore, the solution is Fe
A tennis ball is dropped from 1.3 m above
the ground. It rebounds to a height of
0.943 m.
With what velocity does it hit the ground?
The acceleration of gravity is 9.8 m/s². (Let
down be negative.
Answer in units of m/s.
part 2 of 3
Answer:
2.65m/s
Explanation:
Using the equation of motion:
v² = u²+2a∆S where
v is the final velocity
u is the initial velocity
∆S is the change in distance
a is the acceleration
Given
u = 0m/s
a = 9.8m/s²
∆S = 1.3-0.943
∆S = 0.357m
Substituting the given parameters into the formula
v² = 0²+2(9.8)(0.357)
v² = 0+6.9972
v² = 6.9972
v=√6.9972
v = 2.65m/s
Hence the velocity at which it hit the ground is 2.65m/s
A bumper car with a mass of 240 kg is moving to the right with a velocity of 2.3
m/s. A second bumper car with a mass of 260 kg is moving to the left with a
velocity of 2.7 m/s. After the collision the first car's velocity is 2.9 m/s left, the
velocity of the second car is 2.1 m/s to the right. Prove conservation of momentum.
Assume the surface is frictionless.
Answer:
See the explanation below
Explanation:
To solve this problem we will take the definition of linear momentum, which tells us that momentum is equal to the product of mass by the velocity vector. Since velocity is a vector, we will take the right-hand movement as positive and the left-hand movement as negative, the left-hand members are taken as before the collision and the right-hand members as after the collision
ΣM1 = ΣM2
(m1*v1) + (m2*v1) = (m1*v2) + (m2*v2)
V1 = velocity before the collision [m/s]
V2 = velocity after the collision [m/s]
m1 and m2 = mass of the vehicles [kg]
Therefore:
(240*2.3) - (260*2.7) = - (240*2.9) + (260*2.1)
Resolving this arithmetic operation we will have:
720 - 702 = - 696 + 546
- 150 = - 150
We can see that before the crash and after the crash the momentum is preserved
why are those who take bribery or give bribery considered enemies of the nation?
Which of the following best describes refraction?
A) The blending of a wave a girls room or passes through opening in a barrier
B) The blending of one wave as two or more waves try to occupy the same space at the same time
C)The bending of a wave as it passes at an angle from one material to another
D)The bending of a wave as it reflects at an
angle from a surface
Answer: C Is The Answer
Explanation:
The option that best describes refraction is Option C. The bending of a wave as it passes at an angle from one material to another.
Refraction is the shift in direction induced by a wave's change in speed when it travels from one medium to another. It is the bending of light when it travels via a translucent medium. Refraction can take place in sound waves or water waves.
The statement is in Option A and Option B is incorrect because refraction does not blend but bend.
Similarly, from Option D, refraction does not reflect at an angle from a surface but reflection does.
Therefore, we can conclude that the Option that best describes refraction is seen in Option C, i.e. The bending of a wave as it passes at an angle from one material to another.
Learn more about refraction here:
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How do you find the total number of nodes in a two-source interference pattern?
I know the formula is like Na=d/lambda but apparently, according to my physics teacher, you have to go one step further to find the total number of nodes. But he never showed us how, and I cant find anything online.
Like for example if the distance between the two sources was 20cm and the wavelength was 2cm, then it would be 20/2=10 right? But my teacher said its wrong. And he wont explain why.
I have a test on this tomorrow please help
During the process of cellular respiration, water becomes oxygen. (2 points)
True
False
Answer: False
Explanation:
Hi, I hope this helps!
During cellular respiration, glucose reacts with oxygen to produce carbon dioxide, water and energy.
Answer: False
Explanation:
1.a car sitting at rest on the road
balanced or unbalanced
explain your answer
Answer:
Balanced force
Explanation:
Balanced Forces, When forces are in balance, acceleration is zero. Velocity is constant and there is no net or unbalanced force. ... Although friction is acting on the person, there is no change in velocity and friction is not a net force in this case. Friction is only a net force if it changes the velocity of a mass.
The car is balanced.
If there are any forced acting on it, then those are balanced too.
write about any five usefulness of pressure in our daily life
Answer:
Some common use of air pressure in daily life is inflating tires, playing musical wind instruments, drinking through straw, flushing toilet, drawing water from well, operating barometer, blowing up balloon, breathing, maintaining body shape especially abdomen.
Explanation: )
Answer:
inflating balloon. pressing the switch.blowing straw.drawing water from wellbreathingHope this is helpful and I would appreciate if you add me as brainliest
1) A long distance runner travels 32 miles in a straight line for 4.0 hours.
What is their velocity? (20 pts)
Draw: (1 pt)
Data: (3 pts)
Given:D= 32 miles
T=4 hours
Unknown:S=?
Formula (2 pts)
V=D/T
Substitution of data with units in formulas: (1 pt)
V=3274
Solve (1 pt)
Write down answers with correct units. Circle your answer. (2 pts)
Answer:
3.57632 m/s im not 100% sure but i think thats the answer
Explanation:
At $0.095/kwh, what does it cost to leave a 25 w porch light on day and night for a year?
Answer:
It will cost $20.81
Explanation:
Cost of Electricity
The rate of the cost of electricity is usually expressed in $/KWH because the consumption of electricity is measured in Kilowatts-hour.
If a 25W porch light is on day and night for a full year, the electricity consumption is:
25W*24 H/Day*365 Day/year* 1 year=219,000 WH
converting to KWH: 219,000 WH = 219,000 /1000 KWH = 219 KWH
The rate is $0.095/KWH, thus:
The cost of electricity is 219 KWH*$0.095/KWH= $20.81
It will cost $20.81
A car starts at rest and accelerates at a constant rate for 12 seconds to speed of 30 m/s. What is the total distance traveled in these 12 seconds
Answer:
360 meters
Explanation:
1. Set up a formula. Distance = Speed x Time
2. Plug in given information. d (distance) = 30m/s * 12s
3. Multiply numbers AND units. d = 360m
4. Check that units & numbers make sense.
Speed is a measure of how quickly an object moves.
The speed equation can be rearranged to calculate the distance traveled and the time required.
The total distance traveled in these 12 seconds = 360 m.
What is speed ?Speed is a measure of how quickly an object moves. Use the speed equation to calculate speed: speed = distance divided by time. The speed equation can be rearranged to calculate the distance traveled and the time required.Speed is the rate at which an object moves along a path in time, whereas velocity is the rate and direction of movement. In other words, velocity is a vector, whereas speed is a scalar value.The force of impact increases with the square of the increase in speed, according to physical laws. So, doubling the speed of a car increases the force of impact fourfold.The total distance traveled in these 12 seconds = 30 m/s x12 sec
=360 m.
To learn more about : Speed
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If an element has an atomic number of 28, how many protons does it have in its nucleus?
A car travels from 20-meters to 60-meters in 10 seconds. Calculate the car's speed.
Answer:
8 m/s
Explanation:
All you have to do here is add 20 and 60 (giving you 80) and dividing by 10 seconds. 80/10= 8 m/s
A balloonist drops his camera from a height of 100 m while his balloon is ascending at 5 m/s. How
long did it take to reach the ground?
A car starts to move from point A to B such that its displacement becomes 150m. This
motion was provided by a driving force of 66MN, calculate the Kinetic energy of the
body at B.??
Answer:
sorry I cannot give the answer I know only little bit about it
To calculate the kinetic energy of the car at point B, we first need to determine its velocity at that point. We can use the work-energy principle to relate the work done by the driving force to the change in kinetic energy of the car:
Work done by driving force = Change in kinetic energy
The work done by the driving force is equal to the product of the force and the displacement:
Work done = Force x Displacement = 66 MN x 150 m = 9.9 GJ
The change in kinetic energy is equal to the final kinetic energy minus the initial kinetic energy. Assuming the car starts from rest at point A, its initial kinetic energy is zero. Therefore, the final kinetic energy at point B is equal to the work done by the driving force:
Final kinetic energy = Work done = 9.9 GJ
Note that we converted the force to MN (meganewtons) and the energy to GJ (gigajoules) to match the SI unit system commonly used in physics calculations.