Physics unit 1

Question 1

In which direction does a magnetic field move?

Answer 1

Always from North to South

Question 2

how does a battery make electricity flow

Answer 2

it acts like a pump and provides the force to push the charge around

Question 3

what is current

Answer 3

the flow of charge around a circuit

Question 4

what instrument is used to measure current

Answer 4

an ammeter

Question 5

what is not used up in a circuit

Answer 5

current

Question 6

what is a series circuit

Answer 6

a circuit that is connected in one continuous loop

Question 7

what is a parallel circuit

Answer 7

at some point the circuit splits into 2 branches and the current is split between them before rejoining later

Question 8

what is electrical current

Answer 8

the rate of flow of charge

Question 9

what is voltage

Answer 9

a measure of the energy being carried by electric charges (in a circuit)

Question 10

in a series circuit the current is …

Answer 10

the same

Question 11

in a series circuit the voltage is …

Answer 11

split between components

Question 12

in a parallel circuit the current is …

Answer 12

split

Question 13

in a parallel circuit the voltage is …

Answer 13

equal on each branch

Question 14

what is resistance

Answer 14

a measure of how well a component opposes current.

Question 15

the higher the resistance…

Answer 15

the lower the current

Question 16

what is the equation to calculate resistance

Answer 16

resistance = voltage
______
current

Question 17

what is resistance measured in

Answer 17

Ohms

Question 18

what is the equation for the total resistance in a series circuit

Answer 18

total resistance = R1 + R2 + R3 …..

Question 19

what is the equation for the total resistance in a parallel circuit

Answer 19

total resistance = 1 + 1 + ….
—– —–
R1 R2

Question 20

what is an LDR

Answer 20

light dependent resistor

Question 21

what does an LDR do

Answer 21

it changes resistance with light

Question 22

what is a thermistor / Ntc (negative temperature co - efficient)

Answer 22

a heat dependent resistor that changes resistance with heat levels. the higher the temperature the lower the resistance

Question 23

what is power

Answer 23

the rate of energy transfer/the energy transferred per second

Question 24

what is power measured in

Answer 24

Watts (W)

Question 25

what the equation for power

Answer 25

power = energy ---------- time

Question 26

what is the equation for electrical power

Answer 26

power = voltage x current or power = current x resistance

Question 27

what is a diode

Answer 27

a device that only lets current flow through it in one direction

Question 28

what does LED stand for

Answer 28

light emitting diode

Question 29

name 3 examples of transverse waves

Answer 29

radio waves, micro waves, gamma rays

Question 30

name 3 uses of radio waves

Answer 30

- broadcasting on radio or tv - MRI scanning - communicating with submarines

Question 31

name 3 uses of micro waves

Answer 31

- microwave ovens - satellite communications - Wi-Fi

Question 32

name 3 uses of infra red radiation

Answer 32

- short range communications e.g remote controls - optical fibers - thermal imaging cameras

Question 33

name 3 uses of visible light

Answer 33

- vision - photography - illumination

Question 34

name 3 uses of ultra violet

Answer 34

- security tags - fluorescent lightbulbs - backlights

Question 35

name 2 uses of x-rays

Answer 35

- to detect cancers - x-rays to find broken bones

Question 36

name 2 uses of gamma rays

Answer 36

- industrial sensors - to detect cancer

Question 37

what waves on the EM spectrum contain ionising radiation

Answer 37

ultra violet x-rays gamma rays

Question 38

what is the EM spectrum

Answer 38

the electromagnetic spectrum

Question 39

what is refraction

Answer 39

when a wave passes into a different medium and it changes speed

Question 40

what are fiber optics

Answer 40

(usually) glass cables that can carry communications. the information is sent as electromagnetic radiation (infra red)

Question 41

name 3 uses of optical fibres

Answer 41

- internet - cable TV - phone signals

Question 42

fiber optics are good for ... 1. long range communications 2. short range communications

Answer 42

1. long range communications

Question 43

what kind of material makes light waves slow down

Answer 43

materials that have higher optical densities

Question 44

what kind of material makes light waves slow down

Answer 44

materials that have higher optical densities

Question 45

what is an example of a natural satellite

Answer 45

the moon

Question 46

what is a geosynchronous orbit

Answer 46

the object only returns to the same position every 24hours

Question 47

what is a geostationary orbit

Answer 47

will always orbit above the same position on the earth's surface. orbits round the equator

Question 48

what is 1 disadvantage of a nuclear power station

Answer 48

high decommissioning cost

Question 49

what is 1 disadvantage of a wind farm

Answer 49

it is unreliable

Question 50

what is 1 disadvantage of a coal fired power station

Answer 50

high CO2 emissions

Question 51

state 1 advantage of the national grid

Answer 51

it is a reliable source of electricity all year round

Question 52

give two examples of transverse waves

Answer 52

- water wave - electro magnetic wave

Question 53

what is 1 example of a transverse wave

Answer 53

sound waves

Question 54

what is the frequency of a wave

Answer 54

the number of waves per second

Question 55

what is the amplitude of a wave

Answer 55

the maximum displacement of the wave

Question 56

finish the sentences glass is _____ dense than air when light enters the glass block it ________ ______ the normal. when the light enters the glass block its speed ______

Answer 56

more bends towards decreases

Question 57

what is the equation to work out pressure

Answer 57

pressure = force / area