You construct a water-powered go-cart by attaching a large tank of water to a cart. The water can be forced out a nozzle by connecting a tank of high-pressure air to the water tank. In preparation for your first ride, you position this contraption facing away from a brick wall. You climb on and start spraying the water against the wall. To your delight you accelerate away from the wall and begin to move. When you have moved far enough away from the wall that the stream of water can no longer hit it, you
A) continue to accelerate as the water sprays out the back of the cart.
B) continue to move, but stop accelerating since the water can no longer push against the wall.
C) feel lighter than normal since the water hitting the ground will produce an upward force.
D) continue to accelerate, but less since it takes more force to accelerate a moving object than a stationary one.

Question

Quizplus · Accepted Answer

The cart continues to accelerate due to the principle of conservation of momentum. As water is expelled in one direction, the cart is propelled in the opposite direction, regardless of whether the water hits a wall or not.

You Construct a Water-Powered Go-Cart by Attaching a Large Tank