SS

Question 1

what happens to kinetic energy during breaking

Answer 1

heating to surroundingd

Question 2

longest wavelength

Answer 2

red

Question 3

Explain why an infrared remote control may not switch on the television from behind an armchair but a radio wave remote control always will.

Answer 3

infrared will absorb, blocked, radio go through. have different frequencies

Question 4

transerve waves

Answer 4

moves up and down, right angles

Question 5

wave speed formula

Answer 5

frequency x wavelength

Question 6

radioactivty measure?

Answer 6

geiger

Question 7

2 sources of background radiation?

Answer 7

sun ,or waste

Question 8

Explain what happens in a carbon-14 nucleus when it decays to a nitrogen-14 nucleus

Answer 8

neutron decays to proton, beta emitted.

Question 9

Describe how a student could use the semi-circular glass block and other
apparatus to determine the critical angle for a glass-air boundary

Answer 9

shine ray light into block,
through curved face radius,
change angle, until 90,
measure angle of incidence, repeat

Question 10

how can student extend to find average speed

Answer 10

measure appropriate distance, time use formulas

Question 11

A object is moving at constant speed. Explain why it is not moving with constant velocity.

Answer 11

Velocity is a vector, which has direction, which also changes

Question 12

Explain why fluorine-18 must be produced close to the hospital where it is used.

Answer 12

Has short half-life, used ASAP, after making

Question 13

Explain why the source of alpha radiation is usually inside the body but the
source of gamma radiation can be outside the body

Answer 13

Alpha is a short range, so needs to be close to tumour, gamma is long range, so can get into body, from outside.

Question 14

compare radio and gamma

Answer 14

radio made intentionally, gamma randomly.
radio produced by free electrons, produced in aerials.
gamma from decay, annihilations, due to fission or fusion

Question 15

process for fusion in new star

Answer 15

nebula collapse, due to gravity, GPE turned into KE.

Question 16

Evidence for expansion

Answer 16

red shift
light from distance stars
shifted to red side of EM
wavelength of light is long
source mioving away, galaxies show
expanding increasing rate

Question 17

evidence for beginning at point

Answer 17

CMBR
mirowave radiation left over from begin
increase of velocity with distance
detected from all over sky

Question 18

Describe what is meant by red-shift.

Answer 18

frequency decreasing, star moving away

Question 19

Explain how red-shift provides evidence for the Big Bang theory.

Answer 19

Red shift is further galaxy, more red shifted light is, further galaxies, faster moving, provides evidence space is expanding.

Question 20

White light can split into colours of spectrum. Why in terms of speed?

Answer 20

colours= different wavelengths.
colour=different speeds
refracts in different
amounts

Question 21

In a fusion reaction, two hydrogen nuclei are forced together to form a
helium nucleus. Explain why a very high temperature is needed for this reaction to happen.

Answer 21

High temperature means high energy, overcome force of repulsion, due to having same charge.

Question 22

Explain how the graphite core and the movable rods are used to maintain and control the chain reaction.

Answer 22

neutrons releasedf slower neutrons needed for fission, some fast, control rods move in out, control speed of reaction.
graphite cord (moderator), slows neutrons. moveable, absorb neutrons, make more or few available for fission

Question 23

Describe difference between transverse and longitudinal waves?

Answer 23

transverse has oscillations perpendicular to waves, longitudinal have same direction.

Question 24

How to determine frequency of waves?

Answer 24

measure time 4 waves, to pass fixed point.

Frequency=number of waves/times

Question 25

Explain why red shift supports both theories, but CMB supports only 1?

Answer 25

Both theories predict expanding universe, big bang predicts had beginning, red shift both support expanding, CMB indicates universe, support big bang.

Question 26

half life>

Answer 26

Time taken for activity radioactive isotope to halve

Question 27

How absorbing electron affects proton, and nucleon number of nucleus?

Answer 27

Proton number decreases by 1, mass remains unchanged

Question 28

How can determine average speed of a trolley?

Answer 28

Measures of time between 2 positrons, using stopwatch, measurement of suitable distance, along runway, measurement of vertical height, repeat, find averages, use of correct equation.

Question 29

Create experiment, investigate effect of different surfaces on average speed of trolley

Answer 29

Keep same height, slope, starting point, length of surface, use at least 3 or more surfaces, calculate average speed and repeat.

Question 30

How a reduction in these industrial processes affect temperature of atmosphere

Answer 30

soot make ice black, absorb more infrared radiation
black cause increase temperature, earth absorption of IR, increase in temp.
Reduction in soot, reduce global warming. shiny sulfate, reflect IR radiation

Question 31

Explain how fission of uranium-235 can lead to chain reaction

Answer 31

Causes 2 or 3 neutrons to be release, one or more of these neutrons absorbed by other nuclei, causes further fission of nuclei, releases further, chain

Question 32

nuclear reactor not controlled

Answer 32

reaction slows, fewer fission, impact nucleus, as 1 released.

Question 33

Describe how energy released is used to drive turbine?

Answer 33

Reactant surrounded by coolant, thermal energy from chain reaction heats, hot coolant used generate steam, used to drive turbine/

Question 34

Explain how a nebula may evolve into a main sequence star.

Answer 34

Nebula as cloud of gas, pulled towards each other, temperature increases, enough for nuclear fusion.