questions exam

Question 1

3 factors causes total stopping distance car to be greaer

Answer 1

• driver reaction time slower due to tiredness
  -poor weather condition due to rain
  -poor weather due to icy

Question 2

How does feeling sleepy likely to affect drivers reaction time

Answer 2

it increases it

Question 3

why driver drink alchol is likely to increase chance of being in accident

Answer 3

bceause the driver reaction time increases
(or cuase slower reaction time).

Question 4

(LINK TO LIGHT)why did student use transparent block and not opqaue object

Answer 4

light will pass through an transparent block

Question 5

simlarities of convex and concave lens

Answer 5

both are deminished

Question 6

Driver see haqzard on road and use brakes to stop. Expalain the factor that affect the distance needed to stop a vehilce in emergencey

Answer 6

By condition on road surface as wet/icy road, and conditon of tyres of worns tyres and brales. These cause affect on friction by reduce between tyre and road, and increase braking this causes kinetic energy increase speed.

Question 7

Give 1 simialrties and difference between orbit of earth moon and international space station

Answer 7

similar- both have cirucular orbit
differ- both have different orbital period

Question 8

sun emits visble light, student concludes that visbile light is not abosrbed by the ozone layer. Tell one piece of evidence that show correct

Answer 8

our human eyes detect visble light so it must come through the ozone.

Question 9

why does atmospheric pressure decrease as the student climbs higher

Answer 9

density of the air decrease and the mass of air above student decrease.

Question 10

battery electric car need recharge. suggest 2 factor that affect the distance an electric car can travel before need rechargeing

Answer 10

capacity of battery and speed

Question 11

slide is plastic, why does child become electrically charge when he goes down the slide

Answer 11

friction between child clothign and slide cause elctron transfer as 2 insulators are rubbed together.

Question 12

state one factor that affetcs the braking distance of the car

Answer 12

weather conditon - wet/icy road

Question 13

why and how does the kinetic energy of skier change as accerlate down the slide

Answer 13

increase gravitional potential energy to transofrmed to kinetic energy

Question 14

what is kN worth
3kN=

Answer 14

3000

Question 15

Student remove each piece of modelling clay from oil before dropping the next piece WHY

Answer 15

so that they dont build up at the bottom and all the peices fall the same distance

Question 16

Describe how to use compass to plot the magnetic field pattern around bar magent

Answer 16

1. Place bar magnet and compass on a peice of paper
2. Mark where compass points to
3. Keeping magnet in same place, move compass to marked point
   4.Repet these steps until go back to magnet
4. Join up all the points
5. add arrow in direction from north to south pole
6. repet steps for above and below the bar magnet

Question 17

how is velocity different to spped of aircraft when it travles constant velocity

Answer 17

velocity also includes direction

Question 18

air is taken into the front of the engine and pushed out of the engine, explain the effect this has on egnine

Answer 18

a equal force from the air pushes on the engine in the opposite direction

Question 19

describe + explain lifecycle of star much more massive than the sun

Answer 19

1. stars initially form from a cloud of dust and gas called nebula
   2.the force of gravity pulls the dust and gas together to form a protostar
2. this provides enough thermal energy for the fusion og hydrogen nuclei to form helium nucli
3. when outward pressure of nuclear fusion equals to the gravity pulling eveything inwards it is called main sequence star
4. when hydrogen starts to run out, helium nuclei begin to fuse to form heavier elements up to iron and the star expand to form red super giant
5. the star will eventually collapse and explode in a supernova
6. this creates elememnts heavier than iron and distrivute them throughout universe
7. this leaves bheind a neutron star or a black hole

Question 20

ramp differ angle short and long ramp. Explain one advatge of use long ramp compare to small ramp

Answer 20

long ramp is at smaller angle so less force is needed to get up the ramp.

Question 21

student tested three people, mean distance was 12.8 Why if all people who took the test may not be 12.8 mean distance

Answer 21

Three students tested are not typical

Question 22

compare the model of solar system used now with the old model of solar system

Answer 22

similarities -
-Both model they orbit the moon, and planet in circular.
-The moon orbits the earth and there is only one sun.
Differences -
- in current model, planets orbit the sun whereas old planet orbit earth.
-There is shown of dwarf planet, whereas old model no dwarf planet.
-And 2 more planets.

Question 23

wavelentgh of transverse wave -

Answer 23

wavelength = Q

Question 24

amplitude of transverse wave -

Answer 24

amplitude = R divide 2

Question 25

why is it important that new scientific observations are peer reviewed?

Answer 25

to check the observations are correct

Question 26

give 2 ways that imaged formed by convex lens(larger, point up), is similar to image concave lens

Answer 26

upright virtual

Question 27

in tranverse wave, the direction of oscilloscope is .....

Answer 27

perpendicular to direction of energy transfer by wave

Question 28

describe method to test, the black-coloured flask will emit more infrared radiation than the silver-coloured flask during 10mins of cooling. EQUIP - SILVER FLASK, BLACK FLASK, KETTLE COLD WATER

Answer 28

1. heat wtaer in kettle 2. add an equal volume of hot water to each flask 3. insert a thermoter to each flasj 4. record the inital reading from tempt of thereometer 5. start stopclock 6. record tempt after 10mins from both flask 7. calculate change in tempt + compare the results to test hypothesis

Question 29

when will flask emit infrared radition at the greatest rate and why - 1st/5th/9th min

Answer 29

1st cis there is greatest tempt difference between hot water and surrouding

Question 30

describe what happen after main sequence of star become black dwarf

Answer 30

1. star expand to become red super giant 2. heavier elements are formed by fusion 3. star shrinks to become a white dwarf 4. star cools and stop emitting enrergy

Question 31

describe what happens to star much bigger than sun after main sequence period

Answer 31

1. the star expands to form a red supergiant 2. outer layers explosde as a supernova 3. elemts heavier than iron are formed 4. become a nuetron star 5. if mass larger enough it forms a black hole.

Question 32

car stops as see fallen tree on road. explain what happen to brake distance if the spped doubles

Answer 32

double speed increase kinetic energy, kinetic energy increase by factor of 4. So work done by brakes to stop the car increase

Question 33

what is difference between distance and displacement

Answer 33

distance is scalar, and displacement is vector.

Question 34

total momentum of the 2 cars was not conserved. what does this mean

Answer 34

momentum before does not equal to momenutum after.

Question 35

scientists want to develop seat belt that produce constant force throughout collision. Use idea of momentum why this is better for driver

Answer 35

reduce momenutum of drive so a smaller constnt force would be needed.

Question 36

as aircraft moves, accerlation decrease even though the force is constant, why

Answer 36

as spped increases, air reistance increase. so resultant force is low

Question 37

explain how london eye wheel can move at steady speed. capsules accerlate same time

Answer 37

velocity has direction , and accerlation occurs when the direction of each capsules changes.

Question 38

another factor that can affect resultant force, and what effect it has on LONDON EYE WHEEL

Answer 38

greater the radius, the smaller the resultant force required

Question 39

3 factors could cause total stoppoing distance to be greater

Answer 39

icy road on poor road condition. worn tyres. poor weather conditons raining

Question 40

what happens when : force are increased as pull thin strip of plasticine... and when force are removed....

Answer 40

plastcinine stretches, and stays stretched

Question 41

what happens when : force increasred as push force on strong metal spring..... when force removed...

Answer 41

spring compresses, and return to orginal length

Question 42

what happens when : force are increase as push force on thin plastic ruler.... when force removed..

Answer 42

ruler bends, and return to orginal shape.

Question 43

why this statment wrong ' it will be much safer because driver can react much faster when driving faster than on road mile'

Answer 43

reaction time of driver does not depdend on speed of car

Question 44

local council must decide whether to introduce lower spped limit - what evidence should council collect

Answer 44

monitor number of accident before and after speed limit. and record number of vehicles.

Question 45

student adjusted the ruler to make it vertical, why important (FORC 1 EXPERIEMENT - force and extension on sprng)

Answer 45

to reduce error in measuring the extension of the spring. As ruler of angle would make the measured extension shorter.

Question 46

state 2 ways in whch shape of spring has change as extended

Answer 46

longer and increase gap between coil

Question 47

what happens to kinetic energy of bus as it is braking

Answer 47

kineitc energy transferred by heating to the brakes.

Question 48

applying brakes of the car cause the temperature of brakes increase, why

Answer 48

work done by friciton between brakes and wheels. causes decrease in kinetic energy and increase thermal energy

Question 49

2 ways increase spanner turn effect

Answer 49

longer spanner and use greater force

Question 50

use idea of moment to explain what happeens when child B move closer to pivo on see-saw. As child A and B are sat normlly

Answer 50

the clockwise moment of child B decreases making it less than the anticlockwise moment of child A. so child A move downwards

Question 51

how could person lifting end of pole increase moment

Answer 51

increase the force exerted

Question 52

use longer steel bar would be easier to remove tree stump why

Answer 52

force is applied further from the axis of rotation. so this increase moment of force

Question 53

child pushes the brick to make it tilt. how far must the brick be tilted to fall over

Answer 53

line of action is outside baseline of brick

Question 54

camera uses converging lens to form image, how image is different by lens on magnifying glass

Answer 54

in a camera the image is real not virtual. and inverted not upright.

Question 55

radio wave and microwave are both electrogmagneti wave, travel same speed through air. Give 2 more properties that are same

Answer 55

tranverse travel at same sppeed through a vacuum.

Question 56

thermal image camera work better night than day to track criminals why

Answer 56

at night there is greater tempt difference between people and surroundings. so surrounding emit less infrared than in daytime.

Question 57

describe how the wavelength of the water waves in ripple tank can be measured accurately

Answer 57

use metre ruler to measure across 10 projected waves and then divide by 10.

Question 58

there is no air in space, astronout cant hear from outside spacesuit why

Answer 58

sound cant travel through a vacuum because there is no vibrate

Question 59

it would not be safe to use x-ray to produce unborn child image why

Answer 59

x-ray are ionsing , they will cause mutations

Question 60

describe difference between longitudinal and tranverse wave

Answer 60

the oscillation cause the wave. Tranverse wave is perpendicular to direction of energy transfer. Longitudiinal wave is parallel to direction of energy transfer.

Question 61

describe feature of x-ray and ultrasound, and what happen when enter human born to show image of unborn baby

Answer 61

x-ray are electromagnetic wave and traverse wave. -It is ionising radiation, the x-ray are absorbed by bone and transmitted by tissue. ultrasound has a frequenecy above 20000hertz, and is longitudinal wave. -reflected when it meets a boundary between 2 different media.

Question 62

describe how radiowaves electromagnetic wave, is different from sound wave

Answer 62

it is transverse wave, can travel through vacuum and has greater frequencies. Travels at speed of light.

Question 63

dots on balloon represent galaxies, first small then big balloon. give 1 strneght and 1 weakn representing idea of expanding universe

Answer 63

strnnght - the balloon expands as the dots get further apart weakn - there is a limit to how far the balloon can expand

Question 64

why cant scienctits answer question about 'why was the universe created'

Answer 64

answer involves religious belief

Question 65

how does red-shift from distant galaxies provide evidence for the beginning of the universe

Answer 65

red-shift shows galaxies are moving away from each other. More distant galaxies show bigger redhsift. so more distant galaxies are moving away faster

Question 66

'when observed from earth, there is an increase in the wavelength of light from distant galaxies'. Explain how this supports the big bang theory of the formation of universe

Answer 66

furthest galaxies show the biggest redshift. Meaning that the furthest galaxies are moving faster. So the universe is expanding

Question 67

what is meant by 'redshift' and what does it tell us about distant galaxies

Answer 67

longer wavelength waves so galaxy moving away from earth

Question 68

explain why sun will not go through supernova but star Mira will

Answer 68

only very massive stars become supernova. So mira is large enough but sun too small.

Question 69

over billion of years the amount of hydrogen in star decrease why

Answer 69

converted into helium

Question 70

explain how atoms of heavy element as gold AU, were formed

Answer 70

fusion of other elements during supernova of stars

Question 71

explain how and when atom of different element distributed throughout universe

Answer 71

explostion of supernova at the end of the 'life' of stars.

Question 72

describe how student measure frequenecy of water ripple

Answer 72

count number of waves that passes a point in a certain time

Question 73

when paperclips pulled off magnet, they fall seperareltly. How could you test whether any paper clips have kept magnetism

Answer 73

bring paper clips all together and see if repel or attratcs.

Question 74

explain why nebula stops collapsing as it becomes a main sequence star

Answer 74

gravity causes increase in temperature, this causes fusion of hygroden to form helium. until balance between gravity and fusion

Question 75

2 advantages for adjustable lenses is glasses

Answer 75

dont need replacing if eye sight changes. only need one pair.

Question 76

advantage of use CT than ultrasound scan

Answer 76

CT scan give higher quality image

Question 77

3 core cable must use and not 2 why

Answer 77

it must have earth wire to reduce risk of shock

Question 78

disadvantage bury power cables underground

Answer 78

more difficult to repair