END OF TERM 3 2022
FORM 1 PHYSICS MARKING SCHEME PAPER
SECTION A – 40 MKS
1. The study of matter in relation to energy. 1 mk
2. Career opportunities.
– Engineering (mechanical, electrical, civil, electronics etc)
– Physics teacher
– Pilot.
– Computer scientist.
– Surveyor. (any other relevant) (any three) (1 x 3)
| 3. | Quantity | S.I unit | Symbols | |
| 1 | Luminous intensity P | Candela | Cd P | |
| 2 | Amount of substances | Male P | Mol P |
Both correct – one mark.
only one correct – zero
4. m = 40 g or m = 40 g
= 0.04 kg r = (50 – 40)
v = 50 – 40 = 10 ml
= 10 ml = 10 cm3
= 0.0000 1 m3
z = 0.04 z = 40 = 4 gcm -3
0.00001 10
= 4000 kg /m3 = 4,000 kgm-3
5.(a) Presence of impurities.
(b) Molecule D experiences equal forces in all directions hence zero resultant force.
The surface molecules A, B and D are only pulled inwards and no outward force for
balancing hence under tension.
6. Adhesive force.
Cohesive force.
7.
Density of mixture = mass of mixture
Volume of mixture
Mass of fresh water = 1800 x 1 =1800g
Mass of sea water = 2200 x 1.025 = 2255g
Density of mixture = 2255 + 1800
1800 + 2200
= 1.01375g/cm3
8. Absence of atmospheric pressure.
9. Concrete and steel have the same linear expansivity. They expand and contract at the
same rate without breaking.
10. The flask receives the heat first and expands increasing its capacity later the heat reaches
the liquid which expands at a faster rate than the glass.
11. Alcohol..
12.(a) Large intermolecular distances.
(b) (i) To focus light into the smoke cell.
(ii) To magnify the smoke particles.
(iii) To illuminate the smoke particles to make them more visible.
(c) Movement of molecules from a region of high concentration to a region of low concentration.
13. – Convection requires a medium but between the sun and the atmosphere there is a vacuum.
– Hot particles move upwards from the source.
14. – Length of the rod.
– Thickness / cross-section area of the rod.
– Temperature difference.
(reject type of motorial & amount of heat produced by the heater)
15. Force is defined as a pull or a push
S.I units = Newton (N)
(b) – can make objects change direction of motion
-Can make a stationary object start moving or increase the sped of moving object/cause acceleration
-Slows down or stop a moving object
-Distort (change shape) of an object
SECTION B (30 MKS)
16. (a)
3
17.(a) Wax B – Wood is a poor conductor and all the heat absorbed by the rod is used for
melting the wax but the metal block conducts all the heat away.
(b) Thermometer A
Dull surfaces are better emitters of heat that shinny surfaces.
(c)(i) To make thermometer more accurate / sensitive.
(ii) Quick acting /quick transmission of heat, to the mercury.
(ii) To magnify the scale.
(d) – Has uniform expansitity.
– Has does not wet the surface.
– It is visible/opaque.
– Good conductor of heat.
– Has wide range of temperature
– Very sensitive to heat. (any three)
18. The S.I. unit of measuring weight is Newton and not Kilogram.
19. 1 palm – Length is 15cm long
10 palm – lengths
= (10 x 15)cm
= 150 = 1.5m
100
20. – Hold the rod upright and measure its length using the tape measure.
– Measure the length of its shadow
– Measure the length of the shadow of a tree in the school compound
– Then relate the height of the tree from:
Height of tree
Height of rod
= Length of the shadow of the tree
Length of the shadow of the rod
21. Mass of H2O – 40 – 20 = 20g = 0.02kg
Density of H2O – 1000kg
Volume of H2O = 0.02
1000 = 0.00002m3
Mass of liquid x 50g – 20g = 30g = 0.03kg
Volume = -.0002
Density of liquid = 1500kg/m3
