Forces definitions

Question 1

Definition of Mass

Answer 1

Mass is defined as the amount of matter in an object and is measured in kilograms

Question 2

Definition of Weight

Answer 2

Weight is defined as the force acting on an object due to the pull of gravity and is measured in Newtons

Question 3

Definition of Friction

Answer 3

Friction is the force which opposes motion

Question 4

Newton’s first law

Answer 4

Newton’s first law states: an object will remain at rest or continue in uniform motion unless acted on by a resultant force.

Question 5

Newton’s second law

Answer 5

When an object is acted upon by a resultant force it will accelerate in the direction of the resultant force. The size of the acceleration is proportional to the resultant force and inversely proportional to the mass.

Question 6

Hooke’s law

Answer 6

The extension of the spring is directly proportional to the load applied provided the limit of proportionality is not exceeded.

Question 7

Centre of gravity

Answer 7

The point on an object through which all of its weight appears to act.

Question 8

Conditions of stability.

Answer 8

An object is stable if the vertical line from the centre of gravity falls inside its base.

Question 9

Moments

Answer 9

The product of the force and its perpendicular distance from the pivot.

Question 10

Principle of moments

Answer 10

When an object in equilibrium the sum of the clockwise moments must be equal to the sum of the anticlockwise moments about the same pivot.