Flashcards in ⭐️Topic SP8/SP9-Forces Doing Work And Their Effects Deck (29)

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1

## What is work done?

### The energy transferred by a force

2

## How can you calculate work done?

### Work done (J)= force (N) x distance moved in the direction if the force (m)

3

## Danny is moving a box weighing 300N. He pulls in 3m along a skipping ramp using a force of 200N. Calculate the work done Danny does.

###
E (work done) = F (force) x d (distance)

= 200N x 3m

= 600J

4

## What is power?

### The rate at which energy is transferred

5

## Power is also the rate of doing work...

### When energy is being transferred by forces

6

## What is power’s unit? What does this mean?

### Watt (W) and 1 watt means 1 joule if work done per second

7

## How can you calculate power?

### Power (W) = work done (J) / time taken (s)

8

## What is the force between two objects that are touching called?

### Contact force

9

## Name a pair of contact forces on a boat

### The force from the engine and water resistance as the engine keeps the boat moving as water resistance slows it down

10

## What kind of force is gravity?

### A non-contact force

11

## What are action reaction forces?

### Pairs of forces acting on different objects in opposite directions

12

## How does gravity work on the moon in respect to the earth?

### It causes the two bodies to attract each other

13

## What kind of force is the gravity that that hold the moon and the earth and acts in an opposite direction?

### Action reaction force

14

## What’s a force field?

### The space around an object where it can affect others

15

## Why do the moon and earth effect each other?

### As the moon is within the earth’s gravitational field

16

## Give examples of a force field?

###
-gravitational field

-magnetic field

-electrostatic field

17

## What metals can a magnet attract?

### Iron, nickel, colbat,

18

## How does an electric field effect two objects within it that have the same charge and are close together

### They produce a pair of forces in equal size and acting in opposite direction

19

## What does it mean if a plane is flying at a constant velocity?

### The horizontal and vertical forces on the plane are balanced

20

## What can a scale diagram be used to find?

### The resultant force

21

## Give the steps to drawing a scale diagram in order to find the resultant force

###
-draw arrows at the correct angles to represent forces, length represents the size so you need a scale diagram

-draw lines to make a parallelogram

-the diagonal of the parallelogram is the resultant force and measure this to find the force

22

## How can you use scale diagrams to resolve the forces?

###
-draw a force arrow to scale at the correct angle

-draw a rectangle with sides in directions you’re interested in

-measure the sides of the rectangle for the resolved forces

23

## What is a moment?

### A turning force

24

## How can you find moment of a force?

### Moment ( N m) = force x distance perpendicular to direction of the force

25

## What’s the rule for when a system involving rotational forces is in equilibrium?

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

26

## What’s a lever?

### A bar that pivots about a point and is used to transfer a force

27

## What can gears do?

### Transmit the rotational effect of a force

28

## Gear X has 10 teeth and is connected to gear Y which has 40. How many times will gear X turn for Y?

### 4 times

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