D protons
k12 student here
You get circular motion, where the acceleration is pointing towards the center of the circle, as long as they are constant, and not fluctuating.
-- Light travels straight, not around in a circle. But if it did, it would cover
a distance equal to the length of the equator in about <em>0.13 second</em>.
-- At the speed of sound (in air at standard temperature and pressure),
it would take about <em>32.6 hours </em>to cover the same distance.
The answer is to this question is B