1.	(a)	60	1
for 1 mark
(b)	electrical to light	2
gains 1 mark
	but electricity to light and heat 
gains 2 mark
	anything to heat and light 
gains 1 mark
(c)	(unwanted) heat produced 	1
for 1 mark
[4]

2.	(a)	generator	1
accept dynamo
accept alternator
(b)	(i)	1400	1
ignore units
(ii)	0.3  or  30%	2
any incorrect unit penalise 1 mark
allow 1 mark for the correct use of 600
or 0.3% or 30
 [7]

3.	light;
sound;
heat;
kinetic/movement
for 1 mark each
[4]
4
(a)	(i)	E = 5 × 108 × 3600 × 24 J/day	3
x 4 (for 4 generators) (sequential on P × t)
= 1.73 × 1014 (J/day) 
for 1 mark each
(ii)	2.66 × 1010 × 18 829	2
= 4.86 × 1014 
for 1 mark each
(iii)	Eff = output/input	3
Eff = 1.73/4.86
Eff = 0.36 or worked to a percentage 
for 1 mark each