1.1 Basic Physics

Question 1

How is a Quantity represented

Answer 1

A quantity is represented by a number multiplied by a unit

Question 2

Scalar quantity

Answer 2

has magnitude only

Question 3

Vector quantity

Answer 3

Has magnitude and direction

Question 4

Resolving

Answer 4

Finding the component of a force - we resolve a force into its horizontal and vertical components

Question 5

Moment

Answer 5

The moment of a force about a point is the product of the force and the perpendicular distance from the point to the line of action of the force

Question 6

density

Answer 6

mass/volume (rho = m/v)
Unit: kgm-3

Question 7

Moment (or torque) of a force

Answer 7

The moment of a force about a point is defined as the force × the perpendicular distance from the point to the line of action of the force,
i.e. moment = F × d
Unit: N m

Question 8

The principle of moments

Answer 8

For a system to be in equilibrium, ∑ anticlockwise moments about a point = ∑ clockwise moments about the same point.

Question 9

Centre of gravity

Answer 9

The centre of gravity is the single point within a body at which the entire weight of the body may be considered to act.