Part 1: Conceptual Newton's Laws

Define laws

Conceptual Questions

If you were in a spaceship and fired a cannonball into space, how much force would have to be exerted on the ball to keep it moving once it has left the spaceship?

If an elephant were chasing you, its enormous mass would be most threatening. But if you zigzagged, its mass would be to your advantage. Why?

If suddenly the force of gravity of the sun stopped acting on the planets, in what kind of path would the planets move?

Example of N3

Why does a cannon recoil when it fires a cannonball?

A person drops the ball which falls because the Earth pulls the ball down. What is the reaction force to that?

If a bicycle and a massive truck have a head-on collision, upon which vehicle is the impact force greater? Which vehicle undergoes the greater acceleration?

Example of N2

An elevator (mass = 1000 kg) is supported by a single cable.

When the elevator is at rest, what is the tension in the cable?

The elevator starts to move upwards at 1m/s/s. Is the tension more, less, or the same?

When the elevator is ascending upward at a constant speed, is the tension more, less, or the same as (a)?

The elevator begins to slow as it reaches the proper floor. Is the tension more, less, or the same as (a)?

If a loaded truck can accelerate at four m/s/s and loses its load so it is only half as massive, what acceleration can it attain for the same driving force?

The force of gravity is twice as great on a 2-kg rock as on a 1-kg rock. Why then does the 2-kg rock not fall with twice the acceleration?