Hewitt 35 hw review

The famous Michelson-Morley interferometer experiment showed that the speed of light was

• of the same value in any state of relative motion
• greater if a light source approached an observer
• greater if an observer moved toward a light source
• less if an observer moved toward a light source

If you walk at 1 km/h down the aisle toward the front of a train that moves at 60 km/h, what is your speed relative to the ground?

• 61 km/h
• 59 km/h
• 60 km/h
• 1 km/h

You walk at 1 km/h down the aisle of a trane moving at 60 km/h. Compare your speed relative to the ground vs your speed relative to the Sun. Are they slightly different or very different?

• Slightly! Relative to the Sun, it is nearly 110 km/hr.
• Slightly! Relative to the Sun, it is nearly 1600 km/hr.
• It is not different at all.
• A lot! Relative to the Sun, it is nearly 110,000 km/hr.

What hypothesis did G. F. FitzGerald make to explain the findings of Michelson and Morley?

• The speed of light in a vacuum was a constant in all frames of reference.
• The length of the material in the experiment contracted perpendicular to the direction of motion.
• The length of the material in the experiment contracted in the direction of motion.
• The time of travel of the light beam lengthened for the light moving in the direction of travel.

What classical idea about space and time did Einstein reject?

• Einstein rejected the idea that time is influenced by gravity.
• Einstein rejected the idea that the speed of light in a vacuum is the same in all reference frames.
• Einstein rejected the idea that space and time are coupled.
• Einstein rejected the idea that space and time are independent.

The speed of light in free space is

• the same only in a uniformly moving frame of reference
• a constant if no acceleration is involved
• a constant
• variable with motion of the source or receiver

What is the same in Einstein's first postulate?

• The acceleration of gravity
• The speed of light in the ether
• All laws of nature in all uniformly moving frames of reference
• The speed of time

What is constant in Einstein's second postulate?

• The law of conservation of energy
• The speed of light in the ether
• The speed of light in a vacuum
• The acceleration of gravity

Two events that are simultaneous in one frame of reference

• are simultaneous in all frames of reference
• are simultaneous in a frame moving relative to the first frame
• may or may not be simultaneous in a frame moving relative to the first frame
• are simultaneous throughout space and time

Inside the moving compartment of a rocket (see figure), light travels a certain distance to the front end and a certain distance to the back end of the compartment. How do these distances compare as seen in the frame of reference of the moving rocket?

• The distances travelled by light are the same.
• The distance travelled by light to the back is shorter.
• The distance travelled by light to the front is shorter.
• The distances travelled by light are both zero.