A rocket in space fires its engines continuously until it runs out of fuel. Describe the motion of the rocket.
A) The rocket's speed increases until its engines stop firing, and then coasts in a straight line.
B) The rocket's speed is a constant value until the engines stop firing, and then coasts to a stop.
C) The rocket's speed increases until its engines stop firing, and then coasts to a stop.
D) The rocket's speed does not change, and it continues to move in a straight line.
E) The rocket does not move, as the engines have nothing to push against.

Question

Quizplus · Accepted Answer

In space, there is no air resistance or friction, so when a rocket fires its engines, it will continuously accelerate until it runs out of fuel. Once the engines stop, it will continue to move at a constant speed in a straight line due to inertia.

A Rocket in Space Fires Its Engines Continuously Until It