Physics Paper 1 Questions - Kapsabet Boys Post Mock 2023 Exams

INSTRUCTIONS 

• This paper consists of TWO sections: A and B.
• Answer ALL the questions in sections A and B in the spaces provided.
• ALL working MUST be clearly shown.
• Non-programmable silent electronic calculators and KNEC mathematical tables may be used.

QUESTIONS

Section A (25 marks)
Answer all Questions in this section

1. A measuring cylinder containing only water is placed on an electronic balance. A small, irregularly shaped stone is now completely immersed in the water.
   The diagrams show the equipment before and after the stone is immersed
   
   before the stone is immersed     after the stone is immersed
   calculate the density of the material of the stone? (2 marks)
2. Two candles, a short and a long one were lit and then covered with a tall bell jar as shown below. State and explain which of the candles goes off first. (2 marks)
   
3. The diagram below shows a liquid in glass thermometer
   
   State two ways of increasing the sensitivity of this thermometer (2 marks)
4. A toy boat was placed on the surface of water as shown below.
   
   A piece of camphor was placed on one side of the boat as shown on the diagram. Show the direction of movement of the boat and explain. (2 marks)
5.  A crystal of potassium permanganate was carefully introduced at the bottom of water column held in a gas jar. After sometime, the whole volume of water was coloured. Explain this observation.
   (2 marks)
6. Water flows steadily along a horizontal pipe at a volume rate of m3/s. if the area of cross-section of the pipe is 20 cm². Calculate the velocity of the fluid. (2 marks)
7.  
   1. State the principle of moments (1 mark)
   2. the figure below shows a mobile bird sculpture that has been created by an artist.
      
      M is the center of gravity including its tail but not including the counter weight that will be added later. The mass of the bird and its tail is 1.5 kg. The bird sculpture is placed on a pivot . The artist then add the counter weight at the end E of the tail so that the bird remains stationary in that position shown above
      Calculate the mass of Counter weight (2 marks )
   3. The centre of mass of the sculpture with counter weight is at the pivot. Calculate the upward force acting at the pivot (1 mark)
8.  In the diagram below, find the pressure of the air in the tube X in the mmHg. The liquid shaded is
   mercury and the atmospheric pressure is 760mmHg. (3 marks)
   
9.  In an experiment to estimate the size of a molecule of olive oil, a drop of oil of volume 0.1 2mm³ was placed on a clean water surface. The oil spread into a patch of area 6.0× l0⁴ mm2. estimate the size of a molecule of olive oil (2 marks)
10.  A body is projected vertically upwards from the top of a building with a velocity of 20m/s. Assuming that it lands at the base of the building, sketch the velocity time graph of the motion. (2marks)
11. The figure 5 below shows two cylinders of different cross-sectional areas connected with a tube. The cylinders contains an incompressible fluid and are fitted with pistons P and Q as shown. Fig 5.
    
    Opposing forces Fl and F2 are applied to the pistons until they do not move. If the pressure on the smaller piston is 5Ncm2. Determine the force F2. (2 marks) 

SECTION B (55 marks)
Answer all the questions in this section

12.  
    1. State Archimedes principle (1mark)
    2.  The figure 6 below shows a block of mass 50g and density 2000kg/rn³ submerged in a certain liquid and suspended from a uniform horizontal been by means of a string. A mass of 40g suspended from the other end of the beam puts the system in equilibrium.
       
       
       1. determine the upthrust force acting on the block (3 marks)
       2. calculate the density of the liquid (3 marks)
       3. calculate the new balance point of the 50g mass the 40g mass remains fixed) if the liquid was replaced with another whose density was 1 200kg/m³ (3 marks)
       4. state and explain one application of Archimedes principle (1 mark)
13. The speed of a train, hauled by a locomotive varies as shown below as it travels between two stations along a straight horizontal track.
    
    
    1. Use the graph to determine:
       1. the maximum speed of the train. (1 mark)
       2. The acceleration of the train during the first 2mins of the journey. (2 marks)
       3. The time during which the train is slowing down. (2 marks)
       4. The total distance, in metres, between the two stations. (3 marks)
       5. The average speed in ms-1 of the train. (3 marks)
14. The figure below shows a block of mass 30kg being pushed up a slope by a force P at a constant speed. The frictional force on the block is 20N.
    
    Determine
    1. The value of P (2 marks)
    2.  The work done in moving the 30kg mass up the inclined plane. (2 marks)
    3. On reaching the top of the slope, the block is left to run freely down the slope. Which one of the forces previously acting on the block would then act in the opposite direction (1 mark)
    4.  Determine the acceleration of the block down the slope (2 marks)
    5.  State two factors that affect the final velocity of the block at the bottom of the inclined plane. (2 marks)
    6. Determine the efficiency of the inclined plane (3 marks)
15. 1. Define specific latent heat of fusion (1mark)
    2. You are provided with the following apparatus:
       • A filter funnel
       • A thermometer
       • A stop watch
       •  Ice at 0°C
       • An immersion heater rated P watts
       • A beaker
       • A stand
       • A boss and clamp and • A weighing machine.
         Describe an experiment to determine the specific latent heat of fusion of ice. Clearly state the measurements to be made. (4marks)
    3. 200 g of ice at 0°C is added to 400g water in a well lagged calorimeter of mass 40g.The initial temperature of the water was 40°C. If the final temperature of the mixture is X°C,
       (Specific latent of fusion of ice L = 3.36 x 10⁵ Jkg^-1, specific heat capacity of water, c = 4200Jkg-1K^-1, specific heat capacity of copper = 400 Jkg-1K^-1.)
       1. Derive an expression for the amount of heat gained by ice to melt it and raise its temperature to X°C (2marks)
       2. Derive an expression for the amount of heat lost by the calorimeter and its content when their temperature falls to X°C. (2marks)
       3. Determine the value of X. (3marks)
16.  
    1. The diagram below shows a satellite orbiting the earth at a constant speed.
       
       Explain why the satellite accelerates though it is moving with a constant speed (1mark)
    2. A string of negligible mass has a bucket tied at the end. The string is 60cm long and the bucket has a mass of 45000mg. The bucket is swung horizontally making 6 revolutions per second.
       Calculate:
       1. the angular velocity (2 marks)
       2.  the angular acceleration (3 marks)
       3.  the tension on the string (2 marks)
       4. the linear velocity (2 marks)
    3. State a condition necessary for a body moving on a banked road not to skid. (1 mark)