MID TERM EXAM, TERM I 2017

PHYSICS FORM 2(60mks)

NAME………………..……………………….…………...... ……... ADM NO ………...... CLASS ….…..…

  1. State two ways by which the image formed by a pin- hole camera differ from that formed by a plane mirror (2mks)
  1. The figure below shows aray of light incident on a plane mirror

The mirror is rotated clockwise through an angle of 12o.Determine;

(a)The angle between the normal and the reflected ray after rotation. (2mk)

(b)The angle through which the reflected ray is rotated (1mk)

3. A lamp of height 6cm is placed 24cm in front of a pinhole camera of length 8cm. Calculate the height of the image formed. (3mks)

4. Figures A and B shows two capillary tubes inserted in mercury and water respectively.

Explain the difference in the levels of mercury and water in the capillary tubes. (2mks)

  1. The initial level of water in a burette was 32cm3. Some 20 drops of water each of volume 0.4cm3 are added. Find its final reading. (2mks)
  1. Explain why high flying aircraft need to be airtight and have pressurized cabins for people (1mk)
  1. The figure below shows a diagram whereby air is trapped in a closed limb of a manometer by mercury. The measurements were taken at sea level

Calculate the pressure acting on the air in

a)mmHg(1mk)

b)Pascals (density of mercury=13.6gcm-3, g=10Nkg-1)(3mks)

8. State the effect(s) on the nature of the image formed by a pin-hole camera when;

(i) Screen is moved closer to the pinhole (1mk)

(ii) Pinhole is enlarged (1mk)

9. The figure below shows a uniform cardboard in the shape of a parallelogram.

Locate the centre of gravity of the cardboard

10. The system in the figure below is in equilibrium at room temperature. The system is taken out where the temperature is 20°c higher for some time.

Explain what is observed immediately it is returned to the room (2mks)

11. Explain why it is much easier to loosen a bolt using along spanner than a short one (2marks)

12. A uniform 120m metal rod is pivoted near one of its ends and kept in equilibrium by a spring balance as shown in the figure below

The reading indicated by the spring balance is 2.0N. Work out the mass of the metal rod

(g = 10N/kg)(3mks)

13. The diagram below shows a flask fitted with a glass tube dipped into a beaker containing water at room temperature. The cork fixing the glass tube is tight.

State with reason what would be observed if cold water is poured on to the flask. (2marks)

14. The stability of a body can be increased by increasing the base area and lowering its centre of gravity. State one way of lowering its Centre of gravity (1mk)

15. The figure below shows a wire glass.

(i)State how the stability of the wine glass is affected if it is being filled with wine (1mk)

(ii)Explain your answer in (i) above. (2mk)

16. Explain the reason why a dropping dust particle in a still room does not trace a straight vertical path (1mk)

17. Use the diagram below to answer the questions below.

(i)State the aim of this experiment.(1mk)

(ii) At the start of the experiment, the region below the beaker had no hydrogen gas. The hydrogen gas from a gas generator is now introduced for some time. State with a reason, the observation made. (2mk)

18. State Pascal’s principle of fluid pressure (1mk)

19. The Figure below shows a hydraulic press system using a lever of negligible mass on the side of a small piston pivoted at point P. A force of 100N is applied at R.

(i)Calculate the force F exerted by small piston on the liquid. (2mk)

(ii) Find the weight of the Bale supported by the large piston. (2mk)

20. Two similar razor blades were placed on a wooden block and the other on an iron block as in the figure below.

It was observed that the razor blade on the wooden block is attracted by the magnet while that on the iron block was not. Explain. (2mk)

21. The Figurebelow shows a U- shaped iron core with a current carrying coil wound around its arms. A cardboard is placed on the core and iron fillings sprinkled on top. Sketch on the figure the magnetic field pattern as viewed from the top. (2mks)

22. State two conditions of equilibrium (2mks)

23. The figure below shows a system in equilibrium with the horizontal rate.

AB is a uniform rule of length 1.0m and weight 20N. Calculate the

(i)Weight of block X (2mks)

(ii)Tension in the string PQ. (2mks)

24. The figure shows a current – carrying conductor in a magnetic field direction of force on the wire is as shown by the arrow.

(a)State the polarities of A and B.(2mk)

A _______

B. ______

(b) The force on a conductor carrying a current in a magnetic field can be varied by changing, among others, the magnetic field strength and the magnitude of the current. Name two other factors that can cause the force to vary. (2mk)

25. Given a bar magnet, a steel bar and a string describe a simple experiment to distinguish between the magnet and the steel bar. (3mk)

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