If Zarina is standing at the bottom of a hill and Jax is riding a bicycle downhill towards her, what will Zarina observe about Jax's speed as he approaches her?
Respond very briefly.
Zarina will observe that Jax's speed appears to be increasing as he approaches her. This is due to gravity pulling Jax and his bicycle down the slope, causing them to accelerate as they descend. The longer Jax is on the slope without any opposing force significantly slowing him down (like friction or air resistance), the faster he will go. Therefore, from Zarina's perspective at the bottom, Jax will seem to be moving faster as he gets closer to her.