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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

What do the symbols v u a x t stand for

A acceleration
T time
X distance
U initial velocity