science-physics

Question 1

what is the unit for energy

Answer 1

Joules

Question 2

what is the unit for power

Answer 2

watts

Question 3

what is the unit for mass

Answer 3

kg

Question 4

what is the unit for change in height

Answer 4

metres

Question 4

Kinetic energy comes from

Answer 4

anything moving

Question 5

the unit for speed is

Answer 5

metres per second

Question 6

Gravitational potential happens when

Answer 6

Anything is lifted

Question 6

Thermal energy comes from

Answer 6

anything with temperature

Question 6

Chemical energy is/comes from

Answer 6

food, fuel and batteries

Question 7

Know what happens to some energy every time there is a transfer

Answer 7

Some energy is wasted. This is transferred to the thermal store of the surroundings

Question 7

Elastic potential happens when

Answer 7

Anything stretched or squashed

Question 8

Know the role of insulators

Answer 8

Insulators reduce the rate of energy transfers to the thermal store surroundings

Question 8

Know the difference between renewable and non-renewable energy resources

Answer 8

Renewable resources – easily replenished
Non-renewable resources – finite

Question 9

Know the impact of burning fossil fuels.

Answer 9

Burning fossil fuels releases carbon dioxide causes global warming/climate change

Question 10

Know ways to reduce wasted energy.

Answer 10

Lubrication – reduces friction
Insulation – reduce the rate of energy transfers to the thermal store surroundings

Question 10

Describe the changes in energy stores when:
A person lifts a box
A petrol car is driven
A stone is fired from a catapult

Answer 10

A person lifts a box – chemical store in the persons muscles decreases, gravitational store of the box increases.

A petrol car is driven – chemical store in the fuel decreases, kinetic store of the car increases.

A stone is fired from a catapult – elastic potential store of the catapult decreases, kinetic store of the stone increases.

Question 11

dependent variable

Answer 11

what you measure

Question 11

independent variable

Answer 11

what you change

Question 12

control variable

Answer 12

what you keep the same

Question 13

Know the units for mass and volume.

Answer 13

Know the units for mass and volume. Mass – kg (kilograms) or g (grams)
Volume – m3 (metres cubed) or cm3 (centimetres cubed)

Question 14

Know what makes up the internal energy of a substance.

Answer 14

Internal energy = kinetic energy of particles + potential energy of particles

Question 15

Know the units for current, potential difference, charge, resistance and power

Answer 15

Current - Amps (A)
Potential Difference – Volts (V)
Charge – Coulombs (C)
Resistance – Ohms (Ω)
Power – Watts (W)

Question 16

Know the colour and potential difference of Earth, live and neutral wires in a plug.

Answer 16

Earth wire – yellow and green striped (0V) safety
Neutral wire – blue (0V)
Live wire – brown (230V) A.C.

Question 17

Know the potential difference and frequency of UK mains supply.

Answer 17

230V
50Hz

Question 18

Identify the independent and dependent variable when investigating the effect of length of wire on its resistance.

Answer 18

Independent variable – length of wire Dependent variable – resistance of the wire

Question 19

Know the function of each part of the national grid.

Answer 19

Power stations – generate electricity (not part of the grid) Step-Up transformers – Increase potential difference (V) Power lines – Carry electricity (high voltage, low current) Step-Down transformers – Decrease potential difference (V) so it is safe for homes.

Question 20

Current meaning

Answer 20

The flow of charge

Question 21

Know the difference between a series and parallel circuit.

Answer 21

Series circuit – one path for current to flow Parallel circuit – more than one path for current to flow

Question 22

Know the rules for series circuits.

Answer 22

Current – the same everywhere Potential difference (from the power supply) – shared between components

Question 23

Know how the resistance of thermistors and LDR's change and give examples of when they are used.

Answer 23

as temperature (thermistor) or light intensity (LDR) increases, their resistance decreases

Question 24

Resistance is

Answer 24

How much a material or component opposes current

Question 25

Charge is

Answer 25

The electrons moving around the circuit