S3 EXAM

Question 1

Electrical current

Answer 1

Electric charge transferred per unit time

Question 2

What do charged particles experience ?

Answer 2

Charged particles experience a force in an electric field

Question 3

potential difference

Answer 3

a measure of the energy given to a charge carrier in a curcuit

Question 4

TURD

Answer 4

the temperature of a conductor increases, the resistance of the conductor increases

Question 5

ametere

Answer 5

measure amps in a curcuit

Question 6

votlmeter

Answer 6

measure potential difference in a curcuit

Question 7

ohmeter

Answer 7

measures the resistance in a curcuit

Question 8

transister

Answer 8

an electric switch in a curcuit

Question 9

electrical power

Answer 9

the amount of energy trasfered per unit time

Question 10

effect of an increases in potetial diffrence

Answer 10

an increase in potetial diffrerence across a componant will increase the power developed across that componant

Question 11

appropriate fuses

Answer 11

a 3A fuse should be selected for most appliences rated up to 720W, a 13A fuse for appliences rated over 720W

Question 12

ionistation

Answer 12

the addition or removal of an electron from an atom

Question 13

effect of ionisation on an atom

Answer 13

this will turn a neutrally charged atom positively or negetively charged ion

Question 14

types of radiation

Answer 14

alpha, beta, gamma

Question 15

what happens when radiation is emitted from the nucleus

Answer 15

energy is released, the energy is usally absorbrd by the medium through which the radiation is passing through

Question 16

x-rays can cause ionisation. explain what is meant by ionisation

Answer 16

when an atom gains or loses electrons

Question 17

alpha

Answer 17

helium nucleus
positively charged
slow and heavy
extremely ionising

Question 18

beta

Answer 18

electrons
negetively charged
fast moving

Question 19

gamma

Answer 19

high frequency waves
travel speed of light
no mass no electrical charge
weakly ionising

Question 20

state two factors which can affect the background radiation level

Answer 20

the radon gas found in rocks and radiation that reaches earth from outer space a s cosmic rays

Question 21

radiation safety procedures

Answer 21

limit time exposed to radiation
wear protective clothing
wash hands after using a radioactive source
don’t touch a radioactive source

Question 22

applications of radiation

Answer 22

radiotherapy - gamma rays kill cancer cells and identify tumour
radioactive tracers- gamma rays to help diagnose illnesses
smoke detecter- alpha radiation easily absorbed by smoke detecter

Question 23

activity

Answer 23

the number of nuclei decaying per second

Question 24

absorbed dose

Answer 24

the energy absorbed per unit mass of the absorbing material

Question 25

equivelent dose

Answer 25

the measure harm that could happen by radiation

Question 26

weigting factor

Answer 26

the measure of the biological effects of radiation

Question 27

half life

Answer 27

time for activity to drop yo half its value

Question 28

nucleur fission

Answer 28

nucleur fission happens when the nucleus of an atom is split in two, which causes a large amount of energy. this continues to happen causing a chain reaction

Question 29

nucleur fusion

Answer 29

nucleur fusion is the process which the nuclei of light elements combine or fuse togther, releasing a large amount of energy

Question 30

advantage and disandvantage of fusion

Answer 30

releases a large amount of energy more than nucleur fission | it is hard to acheive and needs large amounts of energy

Question 31

scaler quantities

Answer 31

is magnetude e.g energy distance speed

Question 32

vector quantities

Answer 32

magnitude and direction e.g acceleration, velocity, force

Question 33

velocity

Answer 33

speed of something in a given direction

Question 34

distance

Answer 34

the total length of path travelled

Question 35

displacement

Answer 35

the length and direction of a straight line from start to finish

Question 36

speed

Answer 36

the distance travelled each second

Question 37

instantaneous speed

Answer 37

the speed of an object at any given time | length of card divided by the time to pass through the light gate

Question 38

acceleration

Answer 38

the change in velocity per unit time

Question 39

state the acceleration of 2ms-2

Answer 39

the acceleration of 2ms-2 means that every second, the velocity increases by 2ms-1

Question 40

effect of forces

Answer 40

change the shape of an object change the speed of an object change the direction of a moving object

Question 41

friction

Answer 41

fiction acts between ant 2 surfaces in contact, it acts in the opposite direction to movement

Question 42

how can friction be reduced

Answer 42

reducing surface contact | creating an air gap

Question 43

friction effect on energy

Answer 43

friction causes energy to be transformed the heat energy which is usally lost to surroundings

Question 44

air resistance

Answer 44

a resistive force that can be reduced by steamlining an object

Question 45

balanced forces

Answer 45

when forces are equal in size but opposite in direction they are said to be balanced. this means there in no force and remains at rest or travelling at a consatant speed in a straight line

Question 46

examples of everyday unbalanced forces

Answer 46

friction, air resistance, weight

Question 47

newtons first law

Answer 47

an object will remain at rest or travel at the same speed, in a straight line unless an unbalanced force acts on the object

Question 48

newtons second law

Answer 48

an object will accelerate in the same direction of the unbalanced force acting on it. the magnitude of the acceleration is also porportional to the magnetude of the unbalanced force

Question 49

mass

Answer 49

mass is a measure of the amount of matter in an object. the mass value does not change from place to place

Question 50

weight

Answer 50

a force caused by a gravitational force acting on an objects mass

Question 51

gravitational field strength

Answer 51

is the weight per unit mass

Question 52

newtons third law

Answer 52

if object A exerts a force on object B, then object B will exert an equal, but opposite force on object A

Question 53

if an object is at rest or accelerating in a straight line then it is called ...

Answer 53

terminal velocity or constant speed

Question 54

``` radiation weighting factor: gamma beta alpha fast neutrons thermal neutrons x-ray ```

Answer 54

``` 1 1 20 10 3 1 ```

Question 55

average annual background radiation

Answer 55

2.2 mSv

Question 56

annual effective dose limit for public

Answer 56

1mSv

Question 57

annual effective dose limit for radiation worker

Answer 57

20mSv