PAPER 1- WRONG QUESTIONS

Question 1

equation linking speed, frequency and wavelength:

Answer 1

speed= frequency x wavelength

Question 2

scalar examples:

Answer 2

• charge
• power
• temperature

Question 3

what is meant by an efficiency of 15%?

Answer 3

15% of total energy is transferred usefully

Question 4

fuel used in a nuclear power station:

Answer 4

uranium

Question 5

how is a main sequence star formed from a nebula?

Answer 5

1. nebula is a cold cloud of gas
2. gravity causes cloud to collapse
3. temperature of gas increases
4. creating a protostar
5. main sequence created when fusion starts

Question 6

how does a main sequence star become a white dwarf?

Answer 6

1. hydrogen fusion stops in core
2. core collapses
3. core temperature of star increases
4. star expands to become a red supergiant
5. surface temp of star decreases
6. helium fusion begins;
7. white dwarf formed when helium fusion stops (in core);
8. idea of rest of star released (as a planetary
   nebula);

Question 7

explain why a coil of wire heats up when there is a current in it:

Answer 7

1. coil has resistance
2. electrons transfer as they flow through the coil
3. due to electron collisions with the lattice ions in the coil

Question 8

how is a convection current formed?

Answer 8

1. temperature of air increases
2. air expands
3. density of air decreases
4. warm air rises
5. cool air replaces warmed air
6. process repeats