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A Level Physics Year 1 > Mechanics > Flashcards

Flashcards in Mechanics Deck (169)
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1

What is a scalar quantity?

A quantity that has no direction (just an amount)

2

What is a vector quantity?

A quantity that has magnitude and direction

3

Give 4 examples of scalar quantities

Mass
Temperature
Energy
Distance

4

Give 4 examples of vector quantities

Acceleration
Velocity
Momentum
Displacement

5

What is a bearing?

A 3-digit angle that is measured clockwise from north in degrees

6

How do you find the resultant vector?

By adding 2 or more vectors together

7

How do you find the resultant vector from a scale diagram?

Drawing a scale diagram with all the vectors joining in one line (tip-to-tail), then measuring the length and angle of the resultant vector from the diagram

8

What is displacement?

The position relative to the start position

9

What does cos60 and sin30 equal?

0.5

10

What is an inclined plane?

A slope

11

Which direction does weight always act?

Downwards

12

What is happening when is a body is in equilibrium?

All the forces are balanced (no resultant force)

13

What 2 states can an object in equilibrium be at?

Rest or moving with constant velocity

14

When only 2 forces act on an object, what do they have to be for the object to be in equilibrium?

Equal and opposite (opposite direction)

15

When forces act on an object in equilibrium, what do they form if you draw them tip-to-tail in a scale diagram?

Form a closed loop (a vector triangle)

16

What is the magnitude of a vector?

The size of it (without direction)

17

What is a moment of a force?

The turning point of a force around a point

18

What are 2 moments of equal size acting parallel to each other called?

A couple

19

What is the mass of an object defined as?

The amount of matter in it

20

What is inertia?

A resistance to a change in motion

21

What happens to the inertia if an objects mass is increased?

The greater the resistance to a change in motion will be (larger inertia)

22

What is weight and what is it measured in?

A force measured in newtons

23

Define weight

The force experienced by a mass due to gravity

24

What equation links weight, gravity field strength and mass

W=mg

25

Is weight a scalar or vector quantity?

Vector as it has size and direction

26

What 2 things does the moment of a force depend on?

Size of the force and how far the force is applied from the turning point

27

What equation links moment, force and perpendicular distance from the turning point?

M = fd

28

What does the principle of moment state for a body to be at equilibrium?

The sum of the clockwise moments about any point equals the sum of the anti-clockwise moments at the same point

29

What will happen to an object if the moments aren't balanced?

The object will turn

30

How do levers work?

An effort force acts against a load force by means of a rigid object rotating around a pivot