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- 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)
- Sketch a block and tackle pulley with three movable pulleys in the lower block and two fixed pulleys in the upper block,to give a velocity...(Solved)
Sketch a block and tackle pulley with three movable pulleys in the lower block and two fixed pulleys in the upper block,to give a velocity ratio of 6.
Find:
(i) An effort of 450N is used to raise a load of 2700N. Determine:
- Mechanical advantage (M.A)
- Efficiency of the pulley system.
(ii) If all the wasted energy is used to raise the lower block and the frictional force between pulleys and moving parts is 3.6N; determine the weight of the lower block.
(iii) If the load moved through a distance of 50cm, determine the useful work done by the effort.
Date posted: September 9, 2019. Answers (1)
- The figure below shows a cuboid in two positions. Explain how the stability of the cuboid changes when it is changed from position a to...(Solved)
The figure below shows a cuboid in two positions. Explain how the stability of the cuboid changes when it is changed from position a to b.
Date posted: September 9, 2019. Answers (1)
- The spiral springs shown in the figure below are identical. Each spring has a spring constant K = 200 N/m. Each rod weighs 0.1 N...(Solved)
The spiral springs shown in the figure below are identical. Each spring has a spring constant K = 200 N/m. Each rod weighs 0.1 N and each spring weigh 0.1 N. Determine the total extension caused by the 150 N weight.
Date posted: September 9, 2019. Answers (1)
- A balloon with argon gas of volume 199cm3 at the earth‘s surface where the temperature is 210C, and the pressure 760mm of mercury. If it...(Solved)
A balloon with argon gas of volume 199cm3 at the earth‘s surface where the temperature is 210C, and the pressure 760mm of mercury. If it is allowed to ascend to a height where the temperature is 20C and the pressure 100mm of mercury, calculate the volume of the balloon.
Date posted: September 9, 2019. Answers (1)
- In a faulty mercury-in-glass thermometer it was found that the mercury level stands at 2 cm mark in the tube at 00C and 20cm when...(Solved)
In a faulty mercury-in-glass thermometer it was found that the mercury level stands at 2 cm mark in the tube at 00C and 20cm when in steam above boiling point of water at normal atmospheric pressure. Calculate the temperature when the mercury stands at 13cm mark.
Date posted: September 9, 2019. Answers (1)
- A man whose mass is 80kg stands on weighing machine. When the lift ascends with an acceleration of 2.45m/s2, what is the reading on the...(Solved)
A man whose mass is 80kg stands on weighing machine. When the lift ascends with an acceleration of 2.45m/s2, what is the reading on the scale?
Date posted: September 9, 2019. Answers (1)
- A micrometer screw gauge which had an error of +0.02mm was used to measure the diameter of a spherical marble. If the actual diameter was...(Solved)
A micrometer screw gauge which had an error of +0.02mm was used to measure the diameter of a spherical marble. If the actual diameter was 3.67mm, draw a micrometer screw gauge showing its reading.
Date posted: September 9, 2019. Answers (1)
- State the name of the instrument used to take the following readings;
(i) 10 kg
(ii) 0.00245m(Solved)
State the name of the instrument used to take the following readings;
(i) 10 kg
(ii) 0.00245m
Date posted: September 9, 2019. Answers (1)
- The figure below shows a pair of parallel plates of capacitors connected to a battery. The upper plate is displaced slightly to the left.(Solved)
The figure below shows a pair of parallel plates of capacitors connected to a battery. The upper plate is displaced slightly to the left.
Suggest two adjustments that can be made so as to reduce the effective capacitance.
Date posted: September 9, 2019. Answers (1)
- Four capacitors were connected in a circuit as shown in the figure below. The switch is then closed.(Solved)
Four capacitors were connected in a circuit as shown in the figure below. The switch is then closed.
Determine ;
(i) The effective capacitance
(ii) The total charge
(iii) The energy stored in the combination when the switch is closed.
Date posted: September 9, 2019. Answers (1)
- In an experiment to determine the focal length of a converging lens several values of image distance and the corresponding magnification were obtained. A graph...(Solved)
In an experiment to determine the focal length of a converging lens several values of image distance and the corresponding magnification were obtained. A graph of magnification m against image distance (V) was plotted as shown below.
From the graph determine the focal length of the converging lens.
Date posted: September 9, 2019. Answers (1)
- The figure below represents a pinhole camera.Sketch rays to show the formation of an enlarged image in the camera. Label both the image and the...(Solved)
The figure below represents a pinhole camera.Sketch rays to show the formation of an enlarged image in the camera. Label both the image and the object.
Date posted: September 9, 2019. Answers (1)
- The figure below shows a bar magnet. Point A and B are in front of the magnet.On the axis provided, sketch a graph showing how...(Solved)
The figure below shows a bar magnet. Point A and B are in front of the magnet.
On the axis provided, sketch a graph showing how the magnetic field strength changes from A to B.
Date posted: September 9, 2019. Answers (1)
- A pendulum bob is whirled with uniform speed in a horizontal circle of radius 20cm.The bob describes an arc of length 5cm within 15 seconds.Calculate
i)...(Solved)
A pendulum bob is whirled with uniform speed in a horizontal circle of radius 20cm.The bob describes an arc of length 5cm within 15 seconds.Calculate
i) Angular velocity
ii) The uniform speed of the bob along the circular path
iii) The frequency with the bob moves along the circular path
iv) State why the bob is accelerating yet it moves with the uniform speed along its path
Date posted: September 9, 2019. Answers (1)
- The following set-up was used by a student to determine the relative density of a cork(Solved)
The following set-up was used by a student to determine the relative density of a cork
During the experiment, the following measurements were taken:-
- Weight of sinker in water = w1
- Weight of sinker in water and cork in air = w2
- Weight of sinker and cork in water = w3
(i) Write an expression for the up thrust on cork
(ii) Write an expression for the relative density of the cork
Date posted: September 9, 2019. Answers (1)
- The diagram below shows a wooden log 12m long, density 800kg/m3 and cross-sectional area 0.06m< sup>2floating upright in sea water of density 1.03g/cm3, such that...(Solved)
The diagram below shows a wooden log 12m long, density 800kg/m3 and cross-sectional area 0.06m< sup>2floating upright in sea water of density 1.03g/cm3, such that a third of it is covered by water.
(i) Determine the weight of the block
(ii) The up-thrust on the block
(iii) The minimum weight that can be placed on the block to just make it fully submerged
Date posted: September 9, 2019. Answers (1)