Physics 5

Question 0

What is velocity ?

Answer 0

How fast you are going with a direction

Question 1

What is speed ?

Answer 1

How fast something is going

Question 2

On a distance time graph what is the gradient ?

Answer 2

Speed

Question 3

What does a flat section mean on a distance time graph ?

Answer 3

Stationary

Question 4

If a distance-time graph goes downwards, what is happening ?

Answer 4

Going back to starting point

Question 5

What do curves represent on a distance-time graph ?

Answer 5

Acceleration or deceleration

Question 6

How do you work out the speed with a distance-time graph ?

Answer 6

Vertical line
______________

Horizontal line

Question 7

What is acceleration ?

Answer 7

How quickly the velocity is changing , it can be a change in speed, direction or both

Question 8

Acceleration = ???

Answer 8

Change in velocity
_________________

 Time taken

Question 9

On a velocity time graph, what does a curve or diagonal line mean ?

Answer 9

Increasing / decreasing acceleration

Question 10

What does a straight horizontal line represent on a velocity time graph ?

Answer 10

A steady speed

Question 11

How can you find the acceleration on a velocity-time graph ?

Answer 11

Work out the gradient by dividing the vertical change by horizontal change

Question 12

What is gravitational force ?

Answer 12

The force of attraction between all masses

Question 13

What are two important effects of gravitational force ?

Answer 13

• It makes all things accelerate towards the ground

* It gives everything a weight

Question 14

Are mass and weight the same thing ?

Answer 14

No

Question 15

What is mass ?

Answer 15

The amount of ‘stuff’ in an object, this will be the same even when gravitational force changes

Question 16

What is weight ?

Answer 16

It is determined by the strength of the gravitational force

Question 17

What are weight and mass measured in ?

Answer 17

Weight - newtons

Mass - Kg

Question 18

What formula relates mass and weight ?

Answer 18

Weight = mass x gravitational field strength

Question 19

What is resultant force ?

Answer 19

The overall force on a point or object

Question 20

What does resultant force determine ?

Answer 20

motion, whether acceleration deceleration or stay at a steady speed

Question 21

What happens If the resultant force is zero, when the object is stationary ?

Answer 21

It will remain stationary

Question 22

What happens if there is no resultant force on a moving object ?

Answer 22

It will continue to move at that velocity

Question 23

What is the equation for a non-zero resultant force ?

Answer 23

F = m x a

Resultant force=massxacceleration

Question 24

When two objects interact two forces are exerted, what are they ?

Answer 24

Equal and opposite

Question 25

If the forces are always equal, how do things move ?

Answer 25

Even though the same force is exerted from each object, the forces are acting on different objects. One of the objects could be lighter than the other an therefore move

Question 26

What does friction do ?

Answer 26

Slow things down

Question 27

Why do objects come to a halt gradually when no force is propelling it ?

Answer 27

Because friction always acts in the opposite direction to movement

Question 28

What is drag ?

Answer 28

Resistance from liquids or gases

Question 29

What makes things less affected by drag ?

Answer 29

Being more streamlined

Question 30

True or False - drag always says the same, even when the speed is increased

Answer 30

False, drag increases as speed increases

Question 31

How does terminal velocity occur in fluids (liquids and gases) ?

Answer 31

When and object first begins to fall, gravity is greater than drag, so it accelerates. As the speed increases the drag increases, this gradually reduces the acceleration. Eventually it will no longer accelerate because friction and drag are equal.

Question 32

What is stopping distance ?

Answer 32

The distance covered between a driver recognising a hazard and the vehicle coming to a halt

Question 33

What two factors affect stopping distance ?

Answer 33

Thinking distance and breaking distance

Question 34

Thinking distance is affected by what ?

Answer 34

* Speed - if you're going fast then you'll go further | * How alert you are - bad visibility or being tired can affect this

Question 35

What affects breaking distance ?

Answer 35

* Speed * How good your brakes are * How good your tyres are * How goo the grip is

Question 36

What is work done ?

Answer 36

When a force moves an object, energy is transferred

Question 37

Work done = ?

Answer 37

Force x Distance

Question 38

Gravitational potential energy = ?

Answer 38

Mass x force of gravity x height

Question 39

Kinetic energy = ?

Answer 39

1/2 x Mass x Speed^2

Question 40

Is kinetic energy just speed ?

Answer 40

No it is the measure of mass and speed. A heavy Lorry at a high speed has more kinetic energy than a car of the same speed

Question 41

What is the law of conservation of energy ?

Answer 41

Energy can never be made or destroyed, only converted into different forms.

Question 42

If a car has kinetic energy, because it is moving, how does it lose this energy to stop moving ?

Answer 42

The kinetic energy has to be converted to heat energy as friction between the wheels and brake pads

Question 43

When an object falls the potential energy is converted into what ?

Answer 43

Kinetic energy - this is why the further it falls the faster it goes

Question 44

If work is done to change an elastic object's shape, what is the energy converted into ?

Answer 44

Elastic potential energy, which is then converted into kinetic energy when the object returns to it's original shape

Question 45

What does the formula 'F = k x e' work out ? And what do k and e represent ?

Answer 45

The force needed to extend an elastic object. k represents the spring constant, which varies depending on the object. e is the extension

Question 46

What is power ?

Answer 46

The rate of work being done, a more powerful object transfers a lot of energy in a short time

Question 47

What is the formula for working out power ?

Answer 47

Power = work done divided by time taken

Question 48

What is power measured in ?

Answer 48

Watts

Question 49

One watt is equivalent to what ?

Answer 49

One joule of energy transferred per second

Question 50

Momentum = ?

Answer 50

Mass x Velocity

Question 51

What is the conservation of momentum ?

Answer 51

The rule that the momentum before an event (like a collision) and the momentum after are equal. This is only in a closed system

Question 52

What is a closed system ?

Answer 52

When there are no external forces acting

Question 53

Why do cars make the change in momentum longer with seat belts and airbags ?

Answer 53

Forces cause change in momentum. During a car crash, the passenger's momentum changes very quickly so the forces on the body will be large. By reducing this momentum time the injury is also reduced

Question 54

What are regenerative brakes ?

Answer 54

It acts as a generator, converting the kinetic energy into electrical energy which can be reused. Normal breaks convert kinetic energy to heat energy