Linear motion & angular motion

Question 1

Scalar quantities

Answer 1

Size

• mass
• inertia
• distance
• speed

Question 2

Vector quantities

Answer 2

size and direction

• weight
• acceleration
• deceleration
• displacement
• velocity
• momentum

Question 3

Mass

Answer 3

made up of bone, muscle, fat, tissue and fluid and measured in kg

Question 4

Weight

Answer 4

force on given mass due to gravity.

mass x gravity = weight

Question 5

Distance

Answer 5

the length of the path a body follows when moving from one position to another

Question 6

Displacement

Answer 6

the length of a straight line joining the start and finish points

Question 7

Speed

Answer 7

rate of change of position

speed (m/s) = distance covered (m) / time taken (s)

Question 8

Velocity

Answer 8

rate of change of position with reference to direction

velocity (m/s) = displacement (m) / time taken (s)

Question 9

Acceleration

Answer 9

acceleration = (final velocity - initial velocity) / time taken

Question 10

Momentum

Answer 10

product of mass and velocity of an object

momentum (kgm/s) = mass (kg) x velocity (m/s)

Question 11

Impulse

Answer 11

time it takes a force to be applied to an object or body

Impulse= force x time

Question 12

Angular motion

Answer 12

occurs when a force is applied outside the centre of mass

Question 13

Torque

Answer 13

angular motion occurs as a result of torque- this is a turning force.

Question 14

Newtons 1st law of linear Motion

Answer 14

rotating body will continue to turn about its axis of rotation with constant angular momentum unless and external torque is exerted upon it.

Question 15

Newtons 2nd law of angular motion

Answer 15

rate of change of angular momentum of a body is proportional to the force causing it and the change that takes place in the direction in which the force acts

Question 16

Newtons 3rd law of angular motion

Answer 16

when a force is applied by one body to another, the second body will exert an equal and opposite force on the other body.

Question 17

Angular displacement

Answer 17

smallest change in angle between the start and finishing point of a rotation

Question 18

Angular velocity

Answer 18

The rotational speed of an object and the axis about which the object is rotating

angular velocity (rad/s) = angular displacement (rad) / time taken (s)

Question 19

Angular acceleration

Answer 19

the rate of change of angular velocity over time

angular acceleration (rad s²) = change in velocity (rad/s) / time taken (s)

Question 20

Moment of inertia

Answer 20

the resistance of a body to angular motion (rotation)

moment of inertia (kg m²) = mass (m) x distribution of mass from the axis (m²)

Question 21

Moment of inertia 2 factors:

Answer 21

1. mass of the body
2. distribution of mass from the axis of rotation

Question 22

Angular momentum

Answer 22

the quantity of rotation a body possesses. involves an object or body in motion around an axis

angular momentum (kg m² rad/s) = moment of inertia (kg m²) x angular velocity (rad/s)