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- A student heated some water and noticed that it boiled at 102ºC. State one possible reason for this observation.(Solved)
A student heated some water and noticed that it boiled at 102ºC. State one possible reason for this observation.
Date posted: September 10, 2019. Answers (1)
- State two factors that affect the efficiency of a pulley system.(Solved)
State two factors that affect the efficiency of a pulley system.
Date posted: September 10, 2019. Answers (1)
- The handle of the screw-jack in the figure below is 42cm long and the pitch of the screw is 0.5cm.(Solved)
The handle of the screw-jack in the figure below is 42cm long and the pitch of the screw is 0.5cm.
(i) Calculate the V.R of the screw jack.
(ii) Calculate the effort needed to lift the load of 1188N.
Date posted: September 10, 2019. Answers (1)
- The figure below shows a pulley system with the load rising at uniform speed.(Solved)
The figure below shows a pulley system with the load rising at uniform speed.
From the information given, calculate:
(i) The velocity ratio of the machine.
(ii) Mechanical advantage of the machine.
(iii) Efficiency of the machine.
Date posted: September 10, 2019. Answers (1)
- A trolley of mass 5kg travelling to the right at 2m/s collides head on with another trolley of mass 3kg travelling at 4m/s to the...(Solved)
A trolley of mass 5kg travelling to the right at 2m/s collides head on with another trolley of mass 3kg travelling at 4m/s to the left. Find their velocity after collision if the collision is perfectly inelastic.
Date posted: September 9, 2019. Answers (1)
- When a mass of 2kg is hang from a single spring, the spring extends by a distance x = 5cm. Determine the total extension in...(Solved)
When a mass of 2kg is hang from a single spring, the spring extends by a distance x = 5cm. Determine the total extension in the set up below given that the springs are identical and weightless.
Date posted: September 9, 2019. Answers (1)
- A uniform metre rule is supported by force of 3N and 2N as shown in the figure below.Determine the weight of the half metre rule.(Solved)
A uniform metre rule is supported by force of 3N and 2N as shown in the figure below.Determine the weight of the half metre rule.
Date posted: September 9, 2019. Answers (1)
- Two candles A and B of equal lengths and thickness are joined together and balanced horizontally as shown below. Candle A is lit.State and explain...(Solved)
Two candles A and B of equal lengths and thickness are joined together and balanced horizontally as shown below. Candle A is lit.State and explain what happens after a short time.
Date posted: September 9, 2019. Answers (1)
- The figure below shows a burette that was initially filled to 12ml with a liquid of density 0.8g/cm³.The liquid is allowed to run out for...(Solved)
The figure below shows a burette that was initially filled to 12ml with a liquid of density 0.8g/cm³.The liquid is allowed to run out for some time. If the volume of liquid removed from the burette has a mass of 14g,determine the final reading on the burette.
Date posted: September 9, 2019. Answers (1)
- You are provided with a 12V a.c. source, four diodes and a resistor.
(i) Draw a circuit diagram for full wave rectifier and show the points...(Solved)
You are provided with a 12V a.c. source, four diodes and a resistor.
(i) Draw a circuit diagram for full wave rectifier and show the points at which the output is taken.
(ii) Sketch a graph of voltage against time before rectification.
(iii) Sketch a voltage – time graph after rectification.
(iv) Sketch a voltage – time graph after rectification with a capacitor connected across the resistor in (i)
Date posted: September 9, 2019. Answers (1)
- The figure below shows a system of capacitors connected to 100V supply.(Solved)
The figure below shows a system of capacitors connected to 100V supply.
(i) the value of a capacitor for the whole circuit system.
(ii) the charge through the 6µF capacitor.
(iii) the p.d across of the 8µF capacitor.
Date posted: September 9, 2019. Answers (1)
- Draw the electric field pattern in the figure below.(Solved)
Draw the electric field pattern in the figure below.
Date posted: September 9, 2019. Answers (1)
- A transformer supplies 12V when it is connected to 240V supply of electricity. The output of the transformer is connected to 12V 36W bulb. The...(Solved)
A transformer supplies 12V when it is connected to 240V supply of electricity. The output of the transformer is connected to 12V 36W bulb. The current drawn from the supply by the transformer is 0.5A. Calculate:
(i) the input power of the transformer.
(ii) the current drawn from the transformer.
(iii) The output power of the transformer.
(iv) the efficiency of the transformer
Date posted: September 9, 2019. Answers (1)
- The two free ends of a coil are connected to a center – zero galvanometer. When the north pole of magnet is moved towards the...(Solved)
The two free ends of a coil are connected to a center – zero galvanometer. When the north pole of magnet is moved towards the coil, the pointer deflects in the direction shown in the figure below.
State with a reason the behaviour of the pointer inn the following cases:
(i) The north pole of the magnet is held stationary near P.
(ii) The north pole of the magnet is made to approach the coil from end Q
Date posted: September 9, 2019. Answers (1)
- The figure below represents a displacement – time graph for a wave.Determine the frequency of the wave.(Solved)
The figure below represents a displacement – time graph for a wave.Determine the frequency of the wave.
Date posted: September 9, 2019. Answers (1)
- A ray of light makes an angle of 350 with the glass surface. Calculate the total distance the ray covers through a glass of refractive...(Solved)
A ray of light makes an angle of 350 with the glass surface. Calculate the total distance the ray covers through a glass of refractive index 1.45, given that the width of the glass is 6cm
Date posted: September 9, 2019. Answers (1)
- Complete the following table(Solved)
Complete the following table
Date posted: September 9, 2019. Answers (1)
- 200g of ice at 00C is added to 400g water in a well lagged calorimeter of mass 40g. The initial temperature of the water was...(Solved)
200g of ice at 00C is added to 400g water in a well lagged calorimeter of mass 40g. The initial temperature of the water was 400C. If the final temperature of the mixture is X0C, (Specific latent of fusion of ice L = 3.36 x 105JK/g, specific heat capacity of water, c = 4200J/kg/K, specific heat capacity of copper = 400J/kg/K)
(i) Derive an expression for the amount of heat gained by ice to melt it and raise its temperature to X0C
(ii) Derive an expression for the amount of heat lost by the calorimeter and its content when their temperature falls to X0C.
(iii) Determine the value of X.
Date posted: September 9, 2019. Answers (1)
- Given the following. A filter funnel, a thermometer, a stop watch, ice at 00C, an immersion heater rated P watts, a beaker, a stand, boss...(Solved)
Given the following. A filter funnel, a thermometer, a stop watch, ice at 00C, an immersion heater rated P watts, a beaker, a stand, boss and clamp and weighing machine.Describe an experiment to determine the specific latent heat of fusion of ice. Clearly state the measurements to be made.
Date posted: September 9, 2019. Answers (1)
- The figure below shows dots which were made by a ticker timer – tape attached to a trolley. The trolley was moving in the direction...(Solved)
The figure below shows dots which were made by a ticker timer – tape attached to a trolley. The trolley was moving in the direction shown.
If the frequency used was 60Hz, distance AB = 12cm and BC = 7.2cm, determine
(i) The velocities between AB and BC
(ii) The acceleration of the trolley.
(b) An object is projected horizontally with a velocity of 40m/s at the top of a cliff 100m from the ground. (Take g = 10m/s2)
(i) Calculate the time taken for the object to hit the ground.
(ii) What is the range of the object from the foot of the cliff
Date posted: September 9, 2019. Answers (1)