Flashcards in Section 1 Deck (85):

1

## What’s current base unit

### A

2

## What’s temperatures base SI unit

### K

3

## What’s the base unit for amount of a substance

### Mol

4

## What’s the derived unit for frequency

###
Herts

Hz

5

## What’s the derived unit for force

###
Newton

N

6

## What’s the derived unit for energy

### Joule J

7

## What’s the derived unit for power

###
Watt

W

8

## What’s the derived unit for pressure

###
Pascal

Pa

9

## What’s the derived unit for electric charge

### Coulomb C

10

## What’s the derived unit for electric potential difference

###
Volt

V

11

## What’s the derived unit for electric resistance

### Ohm

12

## What’s the derived unit for magnetic flux density

### Tesla T

13

## Giga

### 10 power 9

14

## Mega

### 10 power 6

15

## Kilo

### 10 power 3

16

## Centi

### 10 power -2

17

## Milli

### 10 power -3

18

## Micro

### 10 power -6

19

## Nano

### 10 power -9

20

## Scalar is

### Has a size or a magnitude

21

## Vector has

### A size or magnitude and a specific direction

22

## Recall some scalar quantities

###
Mass

Speed

Distance

Energy

TenperAture

23

## Recall some vector quantities

###
Force or weight

Velocity

Displacement

Acceleration

Momentum

24

## What is velocity?

### A speed in a stated direction

25

## What’s the equation for average speed?

###
Total distance travelled\total time taken

S=D/T

D=S x T

M/s. M. S

26

## What’s on the axis on distance/time graphs

###
Distance on y

Time on x

27

## What does the gradient of a distance/time graph tell you

### About the motion of the vehicle

28

## If the gradient is a diagonal line what does it tell us

### It’s a constant or steady speed

29

## If the line is curving up wards

### It’s accelerating

30

## If line goes up then starts to curve slowly down

### Deceleration

31

## If like is a horizontal line

### Stationary vehicle

32

## What’s the equation for acceleration

###
= change in velocity

—

33

## Equation including velocity

###
(Final velocity)^2 - (initial velocity)^2 = 2 x acceleration x distance

V^2 - u^2 = 2 x a x X

V^2 = u^2 + 2ax

34

## What do velocity/time graphs show

### How the velocity of a vehicle changes with time

35

## What can you work out with a velocity/time graph

### The acceleration and distance travelled

36

## What’s on each axis on a velocity/time graph

###
Velocity on y axis

Time on x axis

37

## What does the slope or gradient of a velocity/time graph tell you

### The acceleration of the vehicle

38

## How do you work out the distance travelled in a velocity/time graph

### Area under the graph

39

## Difference in distance/time graphs and velocity/time graphs

###
Gradient of d/t tells constant/steady speed

Gradient v/t tells acceleration

Horizontal line on d/t tells you student is stationary

Horizontal line on v/t tells u constant velocity

40

## What equipment can speed be determined with

### Light gates connected to a computer or a data logger

41

## Describe light gate method

###
There a vehicle with a card on it

Vehicle is released from it’s starting position and it moves down the slope

Light gate is attached to laptop

The light beam is cut by the card as it enters the light gate and the timer starts

The beam remains cut until the back of the card passes out of the light gate

When the card leaves the light gate the light beam stops the timer

The speed is found from the length of card\time

42

## How can you measure the speed of falling objects

###
Using light gates

Acceleration due to gravity is

10m/s^2

This means that falling objects will increase its speed by 10 every second when falling in a sense of frictional or resistive forces

However for a piece of falling paper this terminal velocity value will decrease considerably of resistive forces

43

## Speed for walking

### 1.5 m/s

44

## Speed of running

### 3 m/s

45

## Speed of cycling

### 6 m/s

46

## Speed of driving

### 13 m/s

47

## Speed of sound in air

### 330 m/s

48

## Speed of airliner

### 250 m/s

49

## Speed of commuter train

### 55 m/s

50

## Speed of gale-force wind

### 16 m/s

51

## What’s Newton’s first law?

### A body will remain at rest or continue in a straight line at a constant speed as long as the forces acting on it are balanced

52

## According to Newton’s first law what happens when the resultant force on a body is 0?

### Body is moving at a constant velocity or it is at rest

53

## According to Newton’s first law when happens the the body where the resultant force is not 0

### The speed and/or the direction of the body changes

54

## Recall Newton’s second law

###
When a resultant force Acts on a mass then there will be a change in its velocity.

The resultant force determines the size and direction of the subsequent acceleration of the mass

55

## Recall Newton’s second law formula

###
Force = mass X acceleration

F = ma

56

## Formula for acceleration

### Force/ mass

57

## Acceleration is in the same direction as the

### Force

58

## When the resultant force is zero what else is zero

### Acceleration

59

## What’s a negative force

### The object is accelerating backwards or is slowing down

60

## What’s inertial mass

### A measure of how difficult it is to change the velocity of a moving object and is defined as the ratio ‘force over acceleration’

61

## What is weight?

### The force that a body experiences due to its mass and the size of the gravitational field that it is in

62

##
What quantity is weight?

What’s it measured in

###
Vector

Newton’s

63

## Equation for weight

###
Weight=mass x gravitational field strength

W = m x g

64

## What is the weight of an object directly proportional too?

### The value of g, do a mass will weigh more on earth than it does on the moon

65

## How is weight measured?

### With a newtonmeter

66

## What’s mass

### A measure of the amount of matter that is contained within a three-dimensional space

67

##
What quantity is mass

What’s it measured in

###
A scalar

Kilograms

68

## What does gravitational field strength depend on

###
The mass of the body

The radius of the body

69

## When will a body have a large gravitational field strength

###
Large mass

Small radius

70

## Gravitational field strength on earth

### 10 N/kg

71

## Gravitational field strength on moon

### 1.6 N/Kg

72

## Gravitational field strength on Jupiter

### 26 N/kg

73

## Gravitational field strength on Neptune

### 13.3 N/kg

74

## Gravitational field strength on mercury

### 3.6 N/kg

75

## Gravitational field strength on mars

### 3.75 N/kg

76

## Gravitational field strength on neutron star

### 10^12 N/kg

77

## What’s the aim in the core practical investigating force and acceleration

### To investigate the effect of mass on the acceleration of a trolley

78

## What’s the apparatus in investigating force and acceleration of a trolley

###
Trolley

Light gates

Data logger

Card of known length

Slope or ramp

Masses

79

## Why can an accelerating mass greater than 100 g be dangerous in investigating force an acceleration

### May hurt someone if it hits them at speed so must bear in mind when designing investigations

80

## Why is it better to use light gates and other electronic equipment to record values than using a ruler and stopwatch

### Because it’s way more accurate

81

## What’s the method for investigating forces and acceleration

###
Set up apparatus as shown

Set up light gates to take velocity and time readings for you

Record velocity and time for different values of mass on trolley

Work our acceleration by dividing difference velocity by time for card to pass between both gates

If changin mass the slope and gradient need to remain the same

82

## Conclusion of investigating force and acceleration

### The acceleration of trolley does not depend on mass of trolley and will remain fairly constant throughout

83

## Kept points to remember about core practical investigating force and acceleration

###
Acceleration is change in speed/time

Two velocity’s needed

Time difference between readings

Velocity is rate of change of displacement and acceleration is the rate of change of Velocity

Rate means ‘per unit time’

V=changeX / changeT

84

## What core practical involves force and acceleration

### Trolley

85