3.5

Question 1

Newtons first law

Answer 1

A body will remain at rest or continue to move in a straight line at a constant velocity unless an external force acts on it

Question 2

Newtons second law

Answer 2

The resultant force of an object is proportional to the rate of change of momentum of the object, where the change of momentum acts in the direction of force

Question 3

Newton’s third law

Answer 3

If object A exerts a force on object B, then object B will exert an equal and opposite force on object A

Question 4

Conditions of third law

Answer 4

The forces must be of the same type

Forces must be acting in opposite directions on different objects

Question 5

Principle of conservation of momentum

Answer 5

Total momentum before a collision is always equal to the total momentum after the collision (provided that no external forces are involved)

Question 6

Impulse

Answer 6

Product of a force (F) and the time (Δt) for which the force acts

Question 7

Elastic collisions

Answer 7

A collision in which all the momentum and kinetic energy are conserved (no energy is transferred to other forms)

Question 8

Inelastic collisions

Answer 8

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