AQA Physics P1 Unofficial Markscheme 2016

High chance you'd get one for "transverse waves"

so I wouldn't get one for saying they travel at the same speed?

Was the six marker not about the hydroelectric dams but turbines in water?! I talked about damage to habitats and possible flooding as disadvantage.
Are hydroelectric generators the same thing (I know the hill thing has a turbine but I don't know if that's what they were asking)

1. Frequency ( 1)
2. Echoes (1)
3. Spread out, same as or equal to (2)
b) the vibrations are parallel to the direction of energy transfer (2)
4. Expensive as long wires are needed to go around the mountains to reach the home (1)

4b) advantages
constant supply, little variation in output
£30k cheaper than wind turbine
renewable resource
doesn't produce as much noise as wind
no co2

disadvantages
could ruin ecosystem by preventing free movement of fish
may need maintenance unlike wind
lower power output - 8w compared to 10w

wind - advantages
higher average output
needs little maintenance
renewable resource
easily expanded
no co2

disadvantages
eyesore
noise pollution
wind speeds vary, meaning there could be times of under- or oversupply
costs 50k, 30k more than hep (6)

5. Inefficient as less or little energy used to heat food as heat is lost as infrared radiation to the surroundings.(2)

b) uses of microwaves and infrared for communication2)
microwave- phone/ satellite communication (1)
infrared- remote controls?? (?), optical fibres?


Propeties of electromagnetic waves:
- diffract(1)
-refract(1)
- diffract(1)
- travel in a vacuum (1)
- reflected(1)

calculation questions,
-340 m/s (2)
-78 degrees(3)
-6.4 watts(2) then
-question on the first 100 seconds? 0.07 (2)
- efficiency question 0.48 w (2)


6. Fins increase surface area (1) and black are excellent absorbers of heat (1)
7. Cosmic microwave background radiation (1)
b) provides evidence for the big bang theory (1)
or the universe expanding

10. The lower the cost, the more efficient it is because:
- huge difference between e.g panel c and panel a only for an extra 10% efficiency (1)
- (numerical evidence) 8 panel cs will total up to £44 with 80% efficiency (1)

11. Why france will still use nuclear power(2) :
- cost of electricity is cheaper with nuclear than with renewable sources
- produces much more electricity than it actually needs using nuclear power
- produces no greenhouse gases like co2

12. Disadvantages of nuclear power stations(2):
-raw materials are non- renewable
- high decommissioning costs
-produces radioactive waste, (hard to store.)

13. Factors that affect rate of energy transfer of mug(2):
-room temperature so larger difference in temperature of mug and surroundings
-surface area of mug

b) how does energy pass from the mug base?
-conduction, particles gain kinetic energy and collide more frequently,
-passing on their extra kinetic energy to other particles .(2)

c) how is a convection current formed in the mug(4):
-liquid at the bottom is heated and particles gain kinetic energy
-and move away from each other, this makes the liquid less dense
- causing it to rise
-and displace the denser colder air at the top , the denser particles then fall
-heated again (creating a circulation with is convection currents)

14) control variable for the investigation measuring rate of evaporation (1) :
-same beaker
-same type of beaker
-same position in the room
- same thermometer
- to tear the data logger to zero for all three

b) why is the data logger better: (2)
- more accurate, as it's sensitive
- easier to read
- not prone to human error so it's reliable.

Extra bits

why does evaporation cool down liquid (2?)
- energetic particles leave
- lower average particle energy

what would happen if volume of liquid decreases, what affect would it have. (1)
-less volume= less evaporation???