- An immersion heater takes 30 minutes to heat 20kg of water from 250C to 600C. How long would the same heater take to heat the...(Solved)
An immersion heater takes 30 minutes to heat 20kg of water from 250C to 600C. How long would the same heater take to heat the same mass of kerosene through the same temperature range. (Assume no heat is lost to the surrounding).
Specific heat capacity of water = 4200JKgˉ¹Kˉ¹
Specific heat capacity of kerosene = 2200JKgˉ¹Kˉ¹
Date posted: June 3, 2019. Answers (1)
- A ball of mass 100g is dropped from a height of 1.25m above the ground surface.
It rebounds to a height of 1.1m. Calculate
(i) velocity of...(Solved)
A ball of mass 100g is dropped from a height of 1.25m above the ground surface.
It rebounds to a height of 1.1m. Calculate
(i) velocity of the ball before impact.
(ii) force of impact if the ball is in contact with the surface for 0.2S (g = 10N/kg).
Date posted: June 3, 2019. Answers (1)
- The figure below shows a graph of force acting on a body against its velocity as it falls through a liquid.
Determine the terminal velocity of...(Solved)
The figure below shows a graph of force acting on a body against its velocity as it falls through a liquid.
Determine the terminal velocity of the body.
Date posted: June 3, 2019. Answers (1)
- The figure below shows a set-up that can be used to verify Charles law of gases.
(i) State the measurements that should be taken in the...(Solved)
The figure below shows a set-up that can be used to verify Charles law of gases.
(i) State the measurements that should be taken in the experiment.
(ii) Explain how the measurements taken in (i) above can be used to verify Charles law.
Date posted: June 3, 2019. Answers (1)
- The figure below shows a uniform bar in equilibrium under the action of tin forces.
Determine the value of F.(Solved)
The figure below shows a uniform bar in equilibrium under the action of tin forces.
Determine the value of F.
Date posted: June 3, 2019. Answers (1)
- A metal bench feels colder than a wooden one when one sits on it on a cold morning even though both are at the same...(Solved)
A metal bench feels colder than a wooden one when one sits on it on a cold morning even though both are at the same temperature. Explain this observation.
Date posted: June 3, 2019. Answers (1)
- The diagram below shows an empty wine glass.
(a) State the effect on its stability when wine is put into the glass.
(b) Explain your answer in...(Solved)
The diagram below shows an empty wine glass.
(a) State the effect on its stability when wine is put into the glass.
(b) Explain your answer in (a) above.
Date posted: June 3, 2019. Answers (1)
- Complete figure (a) and (b) below by showing the level of the liquids in the glass tubes.(Solved)
Complete figure (a) and (b) below by showing the level of the liquids in the glass tubes.
Date posted: June 3, 2019. Answers (1)
- The figure below shows a sheet of paper rolled into a tube.
When a stream of air at high speed is blown into the tube,...(Solved)
The figure below shows a sheet of paper rolled into a tube.
When a stream of air at high speed is blown into the tube, the paper tube collapses.
Explain this observation.
Date posted: June 3, 2019. Answers (1)
- The figure below shows a wire A and a spring B made of the same material. The thickens of the wire is the same in...(Solved)
The figure below shows a wire A and a spring B made of the same material. The thickens of the wire is the same in both cases. Masses are added on each at the same interval and the extension noted each time. Sketch the graphs of load against extension for each assuming Hookes law is obeyed.
Date posted: June 3, 2019. Answers (1)
- The graph below shows stopping potential V against frequency for a photocell.
From the graph determine:
(i) Threshold frequency
(ii) Planck’s constant
(iii) Work function of the metal...(Solved)
The graph below shows stopping potential V against frequency for a photocell.
From the graph determine:
(i) Threshold frequency
(ii) Planck’s constant
(iii) Work function of the metal
(Takee = 1.6 x 10-19c)
Date posted: June 3, 2019. Answers (1)
- An object is placed 12cm from a convex lens and it forms a virtual image 36cm from the lens
Calculate the focal length of the lens.(Solved)
An object is placed 12cm from a convex lens and it forms a virtual image 36cm from the lens
Calculate the focal length of the lens.
Date posted: June 3, 2019. Answers (1)
- Complete the diagram below indicating the rays that will lead to the formation of the image I shown below and locate the object position.(Solved)
Complete the diagram below indicating the rays that will lead to the formation of the image I shown below and locate the object position.
Date posted: June 3, 2019. Answers (1)
- A student designed a transformer to provide power to an electric bell marked 24W, 6V from a 240V mains. He wound 50 turns and N...(Solved)
A student designed a transformer to provide power to an electric bell marked 24W, 6V from a 240V mains. He wound 50 turns and N turns on an iron ring. When he a connected the coil of 50 turns to the bell and the N turns coil to an a.c, he found that the transformer was only 60% efficient. Find:
(i) The value of N
(ii) The power in the coil with N turns
Date posted: June 3, 2019. Answers (1)
- Use the law to determine the direction of the induced current in the circuit below(Solved)
Use the law to determine the direction of the induced current in the circuit below
Date posted: June 3, 2019. Answers (1)
- The graph below shows the variation of potential difference V with current, I for a certain cell.
From the graph determine:
(i) Internal reaction of the cell....(Solved)
The graph below shows the variation of potential difference V with current, I for a certain cell.
From the graph determine:
(i) Internal reaction of the cell.
(ii) The e.m.f of the cell
Date posted: June 3, 2019. Answers (1)
- The figure below shows an arrangement of capacitor connected to a 10V DC supply.
Determine
(i) The combined capacitance of the arrangement.
(ii) The total energy stored.(Solved)
The figure below shows an arrangement of capacitor connected to a 10V DC supply.
Determine
(i) The combined capacitance of the arrangement.
(ii) The total energy stored.
Date posted: June 3, 2019. Answers (1)
- In the pipe below complete the diagram to show how air in the open pipe vibrates with a frequency of first overtone.(Solved)
In the pipe below complete the diagram to show how air in the open pipe vibrates with a frequency of first overtone.
Date posted: June 3, 2019. Answers (1)
- The figure below shows a set up by a student.
State and explain what happens to the sound from the buzzer as the bottle and its...(Solved)
The figure below shows a set up by a student.
State and explain what happens to the sound from the buzzer as the bottle and its contents are cooled to 0oC
Date posted: June 3, 2019. Answers (1)
- The figure shows a simple cell.
Use the information on the figure to answer the questions below.
(a) Name the parts labeled A and B
(b) It is...(Solved)
The figure shows a simple cell.
Use the information on the figure to answer the questions below.
(a) Name the parts labeled A and B
(b) It is observed that the bulb goes off after a short time. Explain this observation
Date posted: June 3, 2019. Answers (1)