I think that Question 5 is correct but I am unsure about 4 a

I think that Question 5 is correct but I am unsure about 4 and 8. Thanks

QUESTION 1 points Save Answer A street performer tosses a ball straight up into the air (event 1) and then catches it in his mouth (event 2). Among the following observers, who measures the Dilated time interval between the two events? O a person sitting at home watching the performance on TV OA person observing the performance from a moving car the street performer himself O a stationary observer on the other side of the street QUESTION 5 Which one of the following statements concerning the Proper Length of a meter stick is true? O The proper length depends on the reference frame in which it is measured. O The proper length is the length measured by an observer who is moving relative to the meter stick. The proper length is always one meter O The proper length depends on the acceleration of the observer. O The proper length depends on the speed of the observer.

Solution

4) for the dilated time interval , the person must be moving with respect to the person performing the stunt.

hence, the only person that is moving is

A person observing the performance from a moving car.

8)

for the object\'s kinetic energy

kinetic energy = total energy - rest energy

kinetic energy = m * c^2 - m0 * c^2

the kinetic energy is m * c^2 - m0 * c^2