If u shoot a gun on a driving car, or with a bow on a riding horse, are the bullets or arrows faster, and why?

Question

I discussed with my family about this situation. I dont get it

In: Physics

Answer 1

Yes, they are moving faster. As for the “why”, its a case of adding energy. The explosion that propels a bullet adds a certain amount of kinetic energy to the bullet. If its already moving, that kinetic energy is added on top of the energy it already has, resulting in a higher total energy and faster speed.

Note, however, that someone in the car wouldn’t *see* the bullet go faster, because they themselves are moving in the same direction as bullet.

(Also, this is all assuming you fired the bullet in the same direction the car is driving. If you fired it backwards, the bullet would actually move slower because it has to first cancel the kinetic energy pushing it forwards)