Mark scheme for IGCSE Physics (0625/2) – Core Theory November 1999
1(a)volume = l x b x h1
= 8 x 5 x 21
= 80 (cm3)1
(b)line shown at 80 mark1
4
2(a)dot at intersection of AX and BY1
(b)straight line through C and candidate’s centre of mass1
2
3(a)attraction1
(b)repulsion1
(c)attraction 1
(d)nothing1
4
4(a)(i)BC1
(ii)had to lift own weight / overcome gravity 1
(b)(i)greater1
(ii)same ( or greater) work1
less time / faster / power = work/time1
5
5(a)series circuit using recognisable symbols1
correct symbols for switch and cell / battery1
correct symbol for battery1
(b)(i)second bell in parallel with first1
(ii)more current / amps / charge / energy from battery1
6(a)normal clearly and correctly shown 1
angle i correctly marked1
angle r correctly marked1
(b)ray bent upwards1
parallel to incident ray by eye1
5
7Any two from
reference to convection
hot water rises
no convection if heated at the top2
2
8Any three from
nucleus at centre
electrons in outside nucleus
electrons in orbital / shell
number of electrons equals the charge on the nucleus3
3
9(a)(i)fA shown between slit and lens A1
clear and correct indication of distance1
(ii)fB shown between lens B and screen1
clear and correct indication of distance1
(b)(i)Any two of the following pairs
ray from top of O parallel to axis (by eye)
down through F ( ½ mm)
ray from top of O through P ( ½ mm)
continuing straight on
ray from top of O through F’ ( ½ mm), not shown
parallel to axis after lens (by eye)4
(Additional incorrect rays subtract 1 for each)
Both rays bending at centre line / refraction
at both surfaces1
(ii)image in correct position1
(iii)ecf for own image drawn
real1
inverted1
larger1
13
10(a)Any five relevant points
core
coil on right hand limb
coil on left hand limb
iron
primary
secondary
a.c.
input
output
laminations
etcetera5
(b)good conductor / low resistance / reduction of energy loss1
(c)(i)correct rearrangement of equation1
correct substitution1
VS = 30 (V)1
(ii)zero1
(d)the same / a little less because of losses1
11
11(a)any two different properties2
appropriate means of detecting these properties2
(b)idea of a reference point1
idea of a physical event which occurs at one temperature1
(c)steam / boiling water1
1001
melting ice / freezing water1
01
any reference to standard pressure / pure / steam in above1
(d)melting point correctly indicated1
boiling point correctly indicated1
correct region identified1
14
12 (a)air molecules moving (not vibrating)1
randomly 1
rapidly1
(b)molecule moving towards the wall1
molecule bouncing off the wall1
(c)collision 1
with wall1
many1
force / push on wall1
(d)move faster / gain more energy1
more / harder collisions (with wall)1
greater pressure1
12
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