1.	…….. conduction
…….. convection
…….. insulation
…….. radiation
for 1 mark each
[4]

2.	(a)	(i)	hot water rises (not heat)	2
for 1 mark
	due to convection currents
or water expands/becomes less dense on heating
or less dense water rises
any for 1 mark 
(ii)	inside hotter (than outside)	1
for 1 mark 
(iii)	(heat transfer by) conduction	1
for 1 mark
(iv)	surround/cover/insulate tank	2
with poor conductor or named insulator
for 1 mark each
(b)	(i)	air is an insulator/poor conductor	1
for 1 mark
(ii)	convection stopped	2
foam is an insulator/poor conductor
for 1 mark each
3.	(a)	(i)	radiation or infra red	1
do not accept rays
do not accept waves
accept electromagnetic waves
(ii)	good absorber (of heat)	1
to absorb heat (or infrared)
do not accept ‘attract’ or ‘capture’ or soak
(iii)	reduce heat loss (from the panel)	1
accept (good) (heat) insulator
accept stop or reduce conduction
accept stop or reduce convection
accept traps heat
accept keeps water hot

(iv)	to reflect (back into the panel) heat or infrared or Sun’s energy	1
do not accept ‘bouncing’
do not accept reflect Sun
do not accept reflect sunlight or sun’s rays
	radiated or given out by the (black) pipe	1
accept back to pipe
accept reduce heat loss for 1 mark
accept reduce heat loss by radiation for 2 marks
accept stop heat loss by radiation for I mark
(b)	any two points from:	2
•	use of a renewable energy resource
conservation of fuels (or named
fuel)
produces no (atmospheric)
pollution (or named pollutant)
accept any reference to reduced or stoped use of fuel
do not accept ‘fewer power stations’ unless qualified
[7]

4.	(a)	(i)	vacuum	1
do not allow stopper
(ii)	(absence of particles) means no(transfer of energy between) particles	1
for conduction
accept particles or atoms or molecules or electrons
	no movement of molecules for(transfer of energy by) convection	1
accept particles/atoms/electrons
if answer to (a)(i) is correct: then in (a)(ii) have stated
‘conduction and convection both need a medium/particles/materials’ = 2 marks
(If medium is specified, it must be correct, conduction can be solid, liquid or gas, convection must be liquid or gas)
if answer to (a)(i) is incorrect then in (a)(ii) have stated ‘conduction and convection both need a medium...’= 1 mark, unless further qualified by stating about absence of particles, in which case get a second mark.
(b)	(i)	silvered surface	1
accept silver surface
(ii)	silvered is a bad emitter/radiator	1
	surface reflects heat/energy/radiation	1
(at inner and outer surface) or is a bad absorber (of energy)
accept bounces off
[6]