Y1 Ch 07 Definitions

Question 1

Scalar quantity

Answer 1

A quantity which has size only

Question 2

Vector quantity

Answer 2

A quantity which has size and magnitude only

Question 3

Resultant vector

Answer 3

The vector that results from adding two or more vectors in a vector sum.

Question 4

Resolving a vector

Answer 4

Split it into two mutually perpendicular components that add up to the original vector

Question 5

Moment

Answer 5

The force times the perpendicular distance from the pivot

Question 6

Pivot

Answer 6

The point at which an object rotates

Question 7

Equilibrium

Answer 7

An object is in equilibrium when the sum of the forces = 0 and the sum of the turning forces is = 0

Question 8

Centre of mass

Answer 8

The point in a body around which the resultant torque due to the pull of gravity is zero.

Question 9

Couple

Answer 9

A pair of forces that provides a turning force but no transitional movement. They act in opposite directions, are parallel but do not act along the same line.