Flashcards in Topic 4- Forces And Energy Deck (20):

1

## What is the equation for work done?

###
Work done= force x distance

Joules= Newton’s x meters

2

## What is the equation for power?

###
Power= work done/time taken

Watts= joules/seconds

3

## What is the equation for a moment?

###
Moment of a force = force x distance

Newton meters = Newton’s x metres

4

## What does the principle of moments state?

### The sum of the clockwise moments=the sum of the anti-clockwise moments

5

## Name the 8 energy stores

###
Kinetic

Thermal

Chemical

Gravitational potential

Elastic potential

Electrostatic

Magnetic

Nuclear

6

## What happens when a system changes?

### Energy is transferred

7

## What is the equation for efficiency?

###
Useful energy transferred

—

8

## Define power and it’s unit

###
Rate of energy transfer

Watt

9

## What happens when there is more power?

### The more work it does each second

10

## Define force

### A push or pull on an object that is caused by it interacting with something

11

## Name the two types of forces

###
Non contact

Contact

12

## What is Newton’s 3rd law?

### Both objects feel an equal but opposite force

13

## What does a free body force diagram show?

### An isolated body and all the forces acting on it

14

## Define resultant force

### The overall force on an object or point

15

## What do scale drawings do?

### Find resultant forces

16

## What are the 3 steps to drawing a scale drawing?

###
1) draw all the forces acting on an object

2) draw a line from the start of the last force to the end of the last force

3)measure the length of the resultant force on the diagram to find the magnitude of the force and the angle to find the direction

17

## Define moment

### Turning effect of a force

18

## Define a lever

### Levers transfer the turning effect of a force - push one end of a lever down and the rotation around the pivot causes the other end to rise

19

## Define gears

### Circular cogs with “teeth” around their edge

20