Question

1. i am not watching my speed and allow it to creep up to ¼ of the speed of light while driving my sports car through campus. a diligent campus police officer is parked by the side of the road and shines his radar gun at me to check my speed. the microwave pulse from the radar gun leaves his gun going at the speed of light relative to the ground. how fast is the speed of the radar pulse as measured from my car as it speeds away from the officer?

your response history:
incorrect. your answer: a. ¼ of the speed of light

1. score: 0/0.21

incorrect. your answer: d. 1 - 1/4 of the speed of light
you may change your answer and resubmit.
a. ¼ of the speed of light
b. ¾ of the speed of light
c. the speed of light
d. 1 - 1/4 of the speed of light
e. 1 - 3/4 of the speed of light

Explanation:

Step1: Recall the property of light speed

The speed of light in a vacuum is a constant in all non - accelerating reference frames according to the theory of relativity.

Step2: Analyze the situation

No matter the motion of the source (the radar gun) and the observer (the car moving away), the speed of the radar pulse (which is an electromagnetic wave and travels at the speed of light) is always the speed of light $c$.

Answer:

C. the speed of light