Question

Lets say that a fly is flying in a car stationary while the car is not moving. then the car speeds up constantly with the fly still stationary will the car apply some force on the fly to keep it accelerated with the car?

Answer 1

Let's say the fly in hovering in the car when the car moves, there is almost no force that tells the fly's body to move foward with the car. The result? The fly will stay where and say hi to the back of the car, and that's when the force will tell the fly's body that we've moving forward.