Physics multiple choice questions! Please help me!?

Question

I need help on these 4 questions. Thank you

1) To a person who is inside a spaceship moving close to the speed of light, a meter stick held horizontally inside the ship looks

A) longer.
B) shorter.
C) wider in the direction of motion.
D) just the same as always.

2) Relativistic equations for length, energy, and momentum hold true for

A) relativistic speeds.
B) everyday low speeds.
C) both of these.
D) none of these.

3) To calculate how much energy an object contains, you multiply

A) its mass times its acceleration.
B) its mass times the speed of light squared.
C) its mass times its velocity.
D) the force on it times the length of time that force acts.

4) The correspondence principle says that

A) the old theory is correct.
B) the new theory is correct.
C) any new theory must correctly predict observations.
D) any new theory must agree with the old correct theory.

Answer 1

1 near the speed luminal, the plot space-time contracts resulting in a contraction of distances and object. HOWEVER, IF THE OBSERVER AND 'IN SOLIDARITY WITH THE MOTORCYCLE, DO NOT CHANGE NOTICE NO. Therefore, the correct answer is D) just the same as always.



2 For the relativistic equations for the length, energy, and momentum are only valid for relativistic speeds: The correct answer is:

A) relativistic speeds.



3 B) its mass times the speed of light squared.



4 D) any new theory must agree with the old theory correct.

Answer 2

1) As you approach the speed of light, you become more massive and shorter with respect to the direction you're moving. However, you're also in the spaceship, so to you nothing changes. The answer is D).



2) Relativistic equations always hold up. It is only Newtonian equations have that any kind of restriction. So the answer is C), as it must be both of them. At non-relitivistic speeds, the factor gamma becomes closer and closer to 1, so they just "become" Newtonian equations.



3) Einstein's famous equation tell you that E = mc^2, also known as rest energy. So the answer is B).



4) The correspondence principle says that any relitivistic equations in quantum mechanics must still agree with larger bodies. So the answer is D).

Answer 3

A) Amplitude is a measure of what number of molecules are plagued by the vibration of a sound wave. The more molecules the bigger the amplitude and the louder the sound. - So False, given that sound develop with amplitude C) Transverse waves are the displacement of the medium in a perpendicular to the direction of propagation of the wave. A ripple on a pond and a wave on a string are without difficulty visualized transverse waves. - In longitudinal waves the displacement of the medium is parallel to the propagation of the wave. Sound waves in air travels through longitudinal waves like a slinky (discipline of high stress and areas of low pressure). So false - for the reason that sound through air is longitudinal. B)A vibration happens over a single wavelength. Frequency is a measure of how many vibrations arise in a single second. This is measured in Hertz (abbreviation Hz) and straight corresponds to the pitch of a sound. Optimally, men and women can hear from 20 Hz to 20,000 Hz (20 kHz), although with age the extremes of hearing are misplaced. - authentic - since others are false this is actual. But when object is vibrating at a extreme velocity then it's going to be too excessive for the human ear to observe it (extra that 20,000 cycles per sec), nevertheless this object is typically small given that a vibration at this frequency will cause colossal object to shake apart. Most significant objects that vibrate the vibration is simply too gradual and the sound will probably be too low to listen to it.