Mark scheme for IGCSE Physics (0625/2) – Core Theory May 1999
1
2
(a)(i)
(ii)
(b)
3
(a)
(b)
4
(a)
(b)
(c)
5
(a)
(b)
speed = distance/time in any form
20/50
0.4 (cm/s)
1
1
1
3
W1
towards pivot, or equivalent
pivot between W & W 1
closer to W
1
1
1
1
4
middle box ticked
solid molecules vibrating / moving about a fixed position
gas molecules faster, move on one path until collision
1
chemical
heat (or equiv.)
light (or equiv.)
motion OR kinetic
position OR potential
geothermal
1
1
1
1
1
1
6
straight line
through origin
calculate gradient OR R = V/I
1
1
1
3
2
3
6
(a)
(b)
(c)
(d)
dispersion OR refraction
spectrum
red
red
(ideally, “those colours which are not absorbed by the red filter”)
1
1
1
1
4
7
(a)
(b)
coil turns
current-carrying coil in magnetic field experiences turning effect
(allow l for reference to force on current-carrying conductor/coil)
(electric) motor (ignore reference to d.c. or a.c.)
OR galvanometer etc
1
idea of avoiding contamination
idea of preventing radiation getting out
idea of warning of the presence of radioactive material
1
1
1
3
volume = l x w x h
volume of paper = 0.3 x 0.2 x 0.05 OR 0.003 (m3)
density = mass/volume in any form
OR
2.4 or 2.4(stated)
0.3 x 0.2 x 0.05 candidate's volume
800 allow e.c.f. if working shown
1
1
1
(c)
8
9
(a)
(b)
(c)
(a)(i)
(ii)
-1-
2
1
4
1
1
(b)
(c)
(d)(i)
(ii)
(iii)
(iv)
10
(a)
(b)
(c)
(d)(i)
(ii)
11
(a)(i)
(ii)
(iii)
(b)(i)
(ii)
(iii)
(iv)
(v)
12
(a)(i)
(ii)
(iii)
(b)(i)
(ii)
(c)
kg/m3
24N
24 OR candidate's weight substituted at top
0.3 x 0.2 OR 0.06 substituted at bottom
400 allow e.c.f. if working shown
N / m2 OR Pa
half (NOT “less”)
same
half (allow ecf from (i))
half (allow ecf from (i))
1
1
1
1
1
1
1
1
1
1
15
ruler close to spring
measure original length
OR note reading of bottom of spring/other reference
hang load
measure final length
OR note new reading of bottom of spring etc
subtract
straight line sloping up
through origin
straight line through origin, but smaller slope
increases speed OR accelerates
same increase
same force
1
ON DIAGRAM
tube, closed at top
reservoir
mercury at suitable levels in tube & reservoir
appropriate meniscus on mercury (x3)
LABELLING
any 2 from: tube, reservoir, mercury, vacuum, scale
atmospheric pressure
h indicating mercury column
clear & correct indication of distance
5 (cm)
idea of excess pressure
less
L.H. mercury higher than R.H. mercury
LH down, RH up BOTH
bigger
A and H
G and F
B and E
any waveform
reasonably constant “period” (by eye)
reasonably constant amplitude (by eye)
vertical line
different spacing
lady’s “waves” closer together than man’s “waves”
(allow 1 only for: man’s “waves” more irregular shape)
-2-
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
15
1
1
1
1
1
1
1
1
1
9