Newton’s Laws and Momentum

What is Newton’s 1st Law of Motion?

An object will remain at rest or move at a constant velocity unless acted upon by a resultant force

What is Newton’s 3rd Law of Motion?

When 2 objects interact they exert forces on each other that are equal in magnitude, opposite in direction and of the same type of force

What is Newton’s 2nd Law of Motion?

Resultant force acting on an object is proportional to its rate of change of momentum and is in the same direction

F = ma

What 2 sets of units can be used for momentum?

Ns

Kgm/s

How is the momentum of an object calculated?

Mass x velocity

p = mv

What is the principle of conservation of momentum?

The total momentum in a system of interacting objects is constant provided no external force acts

What is an elastic collision?

A collision in which kinetic energy is conserved

What is an inelastic collision?

A collision in which some kinetic energy is transferred to other forms

How is impulse calculated?

Force x time

What is the relationship between impulse and momentum?

Impulse is equal to change in momentum

What is represented by the area under a force-time graph?

Impulse

What is represented by the gradient of a momentum-time graph?

Resultant force

What is the change in momentum when an object of momentum p collides elastically at right angles with a wall?

-2p

When can F = ma be used?

When an object has constant mass