Dynamics

Question 1

Force

Answer 1

A push or pull acting on a body from an external body. Changes the velocity of an object

Question 2

Newton’s 3rd law

Answer 2

When a body A exerts a force on a body B the B exerts an equal and opposite force on A

Question 3

F = ma

Answer 3

the mass x its acceleration is equal to the vector sum (resultant force) of the forces acting on the body

Question 4

momentum

Answer 4

p = mv

Question 5

Newton’s 1st law

Answer 5

An object continues at rest or in uniform motion (constant velocity) unless its acted upon by a resultant force

Question 6

Newton’s 2nd law

Answer 6

The rate of change of momentum of an object is proportional to the resultant force on it and takes place in the direction of that force.

Question 7

Tension

Answer 7

The magnitude of the force that a stretched object exerts on whatever its ends are attached to. This is equal to the magnitude of the force which is applied to the ends of an object to keep it stretched.

Question 8

principle of conservation of momentum

Answer 8

The total momentum of a system of objects is constant provided no external forces act on the system

Question 9

Elastic collision

Answer 9

No kinetic energy is lost or gained (once the bodies have separated)

Question 10

Inelastic collision

Answer 10

A collision in which kinetic energy is lost