**SECTION A** (25 marks)*Answer all the questions in the spaces provided.*

**Figure 1**shows a vernier calipers being used to measure the internal diameter of a tube.

Record the diameter of the tube. (1 mark)- A stop watch started at 0.50s after the start button was pressed. The time recorded using the stopwatch for a ball bearing falling through a liquid was 2.53s. Determine the time of the fall. (1 mark)
- Some water in a tin was boiled for some time. The tin can was then released and cooled. After some time it collapsed. Explain this observation. (2 marks)
- A paper windmill in a horizontal axis was placed above a candle as shown in
**figure 2.**When the candle was lit the paper windmill began to rotate.

Explain this observation. (2 marks) - When a liquid is heated in a glass flask, its level at first falls then rises. Explain this observation. (2 marks)
**Figure 3**shows a uniform metre rule pivoted at the 30cm mark. It is balanced by a weight of 2N suspended at the 5cm mark.

Determine the weight of the metre rule. (2 marks)**Figure 4**shows a horizontal tube with two vertical tubes**x**and**y**. Water flows through the horizontal tube from right to left. The water level in tube**x**is higher than water level in tube**y**.

Explain this observation. (2 marks)- A cart of mass 30kg is pushed a long a horizontal path by a horizontal force of 8N and moves with a constant velocity. The force is increased to 14N.

Determine:- The resistance of the motion of the cart. (1 mark)
- The acceleration of the cart. (2 marks)

- When a drop of oleic acid of known volume is dropped on the surface of water in a large trough, it spreads out to form a large circular patch. State
**one**assumption made when the size of the molecule of the oleic acid is estimated by determining the area of the patch. (1 mark) - The weight of a solid in air is 5.0N. When fully immersed in a liquid of density 800Kg m
^{-}3, its weight is 4.04N.

Determine:- The upthrust in the liquid. (1 mark)
- The volume of the solid. (2 marks)

- When a bicycle pump was sealead at the nozzle and the handle slowly pushed toward the nozzle, the pressure of the air inside increased.

Explain this observation. (1 mark) **Figure 5**shows a mass of 200g connected by a string through a hollow tube to a mass of 0.50kg, The 0.5kg mass is kept stationery in the air by whirling the 200g mass around in a horizontal circle of radius 1.0 metre.

Determine the angular velocity of the 200g mass. (3 marks)- State the SI unit of a spring constant. (1 mark)
**Figure 6**shows an athlete lifting weights while standing with the feet apart.

Explain why standing with the feet apart improves the athletesâ€™ stability. (1 mark)**SECTION B**(55 marks)*Answer***all**the questions in this section in the spaces provided.- A cyclist initially at rest moved down a hill without pedaling. He applied brakes and eventually stopped. State the energy changes as the cyclist moved down the hill. (1 mark)
**Figure 7**shows a mass of 30kg being pulled from point P to point Q, with a force of 200N parallel to an inclined plane. The distance between P and Q is 22.5m. In being moved from P to Q the mass is raised through a vertical height of 7.5m.- Determine the work done:
- by the force; (2 marks)
- on the mass; (2 marks)
- to overcome the friction. (2 marks)

- Determine the efficiency of the inclined plane. (2 marks)

- Determine the work done:
- Suggest one method of increasing the efficiency of the inclined plane. (1 mark)

- In the experiment to determine the density of sand using a density bottle, the following measurements were recorded:

Mass of empty density bottle = 43.2g

Mass of density bottle full of water = 66.4 g

Mass of density bottle with some sand = 67.5 g

Mass of the density bottle with the sand filled up with water = 82.3g

Use the data to determine the:- Mass of water that completely filled the bottle; (2 marks)
- Volume of water that completely filled the bottle; (1 mark)
- Volume of the density bottle; (1 mark)
- Mass of sand; (1 mark)
- Mass of water that filled up the space above the sand; (1 mark)
- Volume of the sand. (3 marks)
- Density of the sand. (2 marks)

- Explain why it is advisable to use a pressure cooker for cooking at high altitudes. (2 marks)
- Water of mass 3.0kg initially at 20
^{0}C is heated in an electric kettle rated 3.0 KW. The water is heated until it boils at 100^{0}C. (*Take specific heat capacity of water*4200Jkg^{-1}K^{-1},*Heat capacity of the kettle*450JK -1,*Specific latent heat of vapourisation of water*=2.3mJkg^{-1})

Determine:- The heat absorbed by the water; (2 marks)
- Heat absorbed by the electric kettle; (2 marks)
- The time taken for the water to boil; (3 marks)
- How much longer it will take to boil away all the water. (3 marks)

**Figure 8**shows the mass of a stone of mass 4.0kg immersed in water and suspended from a spring balance with a string. The beaker was placed on a compression balance whose reading was 85N. The density of the stone was 3000kgm^{-3}while the density of the liquid was 800kgm^{-3}.

Determine the:- Volume of the liquid displaced. (2 marks)
- Upthrust of the stone. (4 marks)
- Reading of the spring balance. (2 marks)
- Reading of the compression balance when the stone was removed from the water. (2 marks)

**Figure 9**shows the velocity-time graph for the motion of a certain body.

Describe the motion of the body in the region:- OA; (1 mark)
- AB; (1 mark)
- BC. (1 mark)

- A moving car initially at 10 ms
^{-1}decelerates at 2.5 ms^{-2}.- Determine:
- its velocity after 1.5s; (2 marks)
- the distance travelled in 1.5s; (2 marks)
- the time taken for the car to stop. (2 marks)

- Sketch the velocity-time graph for the motion of the car up to the time the car stopped. (1 mark)
- From the graph, determine the distance of the car travelled before stopping. (2 marks)

- Determine:

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