Mark scheme for IGCSE Physics (0625/2) – Core Theory May/June 2000
1
(a)
(b)
(c)
weight
mass
greater density OR less air gaps between potatoes
2
(a)
Any three from:
conduction
convection
radiation
evaporation
suitable procedure
correct form of heat loss for candidate’s procedure
(b)(i)
(ii)
3
(a)
(b)
4
(a)
(b)(i)
(ii)
(c) (i)
(ii)
5
(a)
(b)(i)
(ii)
(c)
1
1
1
3
3
1
1
5
wind wire round iron bar
both ends of coil connected to battery
extra valid point e.g. cut off length of wire, strip ends etc.
suitable check e.g. picking up iron(filings)
deflects compass needle
repels another magnet
move into coil connected to galvanometer
1
1
1
refraction (allow slowing down of light/ angle of refraction)
normal correct, by eye
i “correctly” shown between candidate’s normal and ray
refraction away from normal
along ST
1. (total internal) reflection
2.angle in water> critical angle
1
1
1
1
1
1
1
7
idea that light travels faster than sound
extra detail
e.g. light travels extremely fast / much faster than sound /
instantaneously / at 3x 108 m/s
1
echo OR equivalent
idea of absorption of sound / dispersion / diffraction /
sound has travelled further / lower air density at altitude
speed = distance/time in any form
(distance = ) approximately 330 x 4
1320(m)
1
1
4
1
1
1
1
1
7
6
(a)(i)
(ii)
(b)
smoke particles ticked
3rd box ticked
4th box ticked
1
1
2
4
7
(a)(i)
(ii)
(iii)
potential OR stored OR position OR gravitational (potential)
kinetic OR motion OR movement
turbine(s) OR coil(s) OR blade(s) OR rotor / fins / wheel
electrical / electricity
1
1
1
1
1
(b)
Any two from:
waves
tides
steam
geothermal
2
6
8
(a)(i)
(ii)
(b)(i)
(ii)
(c)
(d)
(e)
(f)
320
candidate’s value correctly plotted ± ½ small square
160
candidate’s value correctly plotted ± ½ small square
points plotted at (60,80)and (80,40) ± ½ small square
smooth curve through candidate’s points, by eye
either of last two boxes ticked
randomness OR idea of background
1
1
1
1
1
1
1
1
8
9
(a)(i)
(ii)
D
large(st) area
least pressure / pressure more spread out
increases
decreases
length AB
√
width BC
√
thickness CD
√
area touching the
horizontal surface
√
mass of sheet
weight of sheet
density of metal
√
pressure on surface
√
1
1
1
(b)
10
(a)
(b)(i)
(ii)
(c) (i)
(ii)
11
(a)
(b)
(c)
(d)(i)
(ii)
12
(a)(i)
(ii)
(b)(i)
stays the same
1
√
√
1
1
1
1
1
9
R = V/l in any form
12/1.5
8Ω
12(V)
0.75 (A)
16(Ω) OR 2 x candidate’s (a), correctly evaluated
16 (Ω/m) OR candidate’s (b)(ii)
64/candidate’s(ci)
4 (m) OR 64/candidate's (ci) correctly evaluated
1
1
1
1
1
1
1
1
1
9
sound
infra-red
X-rays
no air / vacuum on the moon implied
1. sound needs a medium/air
2. radio waves don’t need a medium/air
radio / μ wave
1
1
1
1
1
1
1
7
B
greater force / weight / heavier
reference to formula or constancy of length
B
1
1
1
1
2
(ii)
(c)
(d)(i)
(ii)
greater weight / force / heavier
reference to formula or constancy of height lifted
weight (of hammer) OR mass OR force
time (to lift)
energy of motion OR K.E.
Any two from:
heat. OR frictional
sound
K.E. of nail
3
1
1
1
1
1
2
11