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- A charge of 4.8C flows through a lamp every second. Calculate the number of electrons involved per second.(Solved)
A charge of 4.8C flows through a lamp every second. Calculate the number of electrons involved per second.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a ray of light incident on a water-air interface from a source 8m deep.
i) Ray A is observed to bend as...(Solved)
The figure below shows a ray of light incident on a water-air interface from a source 8m deep.
i) Ray A is observed to bend as it enters the air. Give a reason why this occurs
ii) If the refractive index of water is 1.35, calculate the angle of refraction of ray A
iii) Find the critical angle of water
iv) Give a reason why ray B is not travelling out of water
v) A fish is placed at the source of light ray. Calculate the maximum area of view on the surface of water
Date posted: May 31, 2019. Answers (1)
- The figure below shows a simple electric motor. Study the figure and answer the questions that follow.
i) Indicate on the diagram the direction of rotation...(Solved)
The figure below shows a simple electric motor. Study the figure and answer the questions that follow.
i) Indicate on the diagram the direction of rotation of the coil.
ii) Explain how the motor works specifying clearly the functions of the parts P and Q.
iii) State one way by which the speed of this motor can be increased.
Date posted: May 31, 2019. Answers (1)
- The figure below shows two parallel conductors P and Q carrying current in the same direction.
On the same figure;
i) sketch the magnetic field pattern
ii)...(Solved)
The figure below shows two parallel conductors P and Q carrying current in the same direction.
On the same figure;
i) sketch the magnetic field pattern
ii) Indicate the force F due to the current on the conductor
Date posted: May 31, 2019. Answers (1)
- The graph in the figure below shows variation in activity of a sample of a radioactive material.
Use the graph to determine the half life of...(Solved)
The graph in the figure below shows variation in activity of a sample of a radioactive material.
Use the graph to determine the half life of the sample
Date posted: May 31, 2019. Answers (1)
- The diagram below shows an object placed in front of two mirrors inclined to each other at an angle x
An observer sees five images, determine...(Solved)
The diagram below shows an object placed in front of two mirrors inclined to each other at an angle x
An observer sees five images, determine the value of angle x?
Date posted: May 31, 2019. Answers (1)
- The figure below Shows a source of beta particles and a detector being used to check the thickness of paper in a paper mill.
i) Explain...(Solved)
The figure below Shows a source of beta particles and a detector being used to check the thickness of paper in a paper mill.
i) Explain how the device works.
ii) Explain why beta particles are used instead of alpha particles or gamma rays.
Date posted: May 31, 2019. Answers (1)
- The diagram below shows waves being diffracted.
What adjustments should be done to obtain the wave form below?(Solved)
The diagram below shows waves being diffracted.
What adjustments should be done to obtain the wave form below?
Date posted: May 31, 2019. Answers (1)
- The figure below shows a section of a house wiring.
i) Name
The circuit labelled X
The terminals A and B.
ii) State the function of P...(Solved)
The figure below shows a section of a house wiring.
i) Name
The circuit labelled X
The terminals A and B.
ii) State the function of P in the circuit.
iii)Give a reason why P is on A but not B.
iv) Explain why earthing is necessary in such a circuit.
Date posted: May 31, 2019. Answers (1)
- Gamma, radio, infrared, x-rays are part of the electromagnetic spectrum.
i) Arrange these radiations in order of increasing energy
ii) State how radio waves are detected(Solved)
Gamma, radio, infrared, x-rays are part of the electromagnetic spectrum.
i) Arrange these radiations in order of increasing energy
ii) State how radio waves are detected
Date posted: May 31, 2019. Answers (1)
- The diagram below shows a current carrying conductor placed in a magnetic field.
i) Show on the diagram the direction of force on the conductor
ii)...(Solved)
The diagram below shows a current carrying conductor placed in a magnetic field.
i) Show on the diagram the direction of force on the conductor
ii) If the current through the conductor is reduced, state and explain what happens to the force in (i) above.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a three pin plug wired by a student and connected to an appliance rated 1000W, 240V.
State two mistakes made by the...(Solved)
The figure below shows a three pin plug wired by a student and connected to an appliance rated 1000W, 240V.
State two mistakes made by the student in the wiring.
Date posted: May 31, 2019. Answers (1)
- A photo sensitive cathode of work function 2.1 eV is illustrated with a radiation of wavelength 4.5× 10-7. Determine the stopping potential for the cathode....(Solved)
A photo sensitive cathode of work function 2.1 eV is illustrated with a radiation of wavelength 4.5× 10-7. Determine the stopping potential for the cathode. Speed of light C = 3.0 × 108m/s,1 eV = 1.6 × 10-19j,
h = 6.6 × 10-34Js.
Date posted: May 31, 2019. Answers (1)
- The figure shows an apparatus used to investigate photoelectric effect.
i) Name the parts A and B.
ii) State the function of C.(Solved)
The figure shows an apparatus used to investigate photoelectric effect.
i) Name the parts A and B.
ii) State the function of C.
Date posted: May 31, 2019. Answers (1)
- The figure shows a loudspeaker producing sound waves in air.
i) Explain how compression and rarefactions are formed.
iii) The wavelength of the waves produced is...(Solved)
The figure shows a loudspeaker producing sound waves in air.
i) Explain how compression and rarefactions are formed.
iii) The wavelength of the waves produced is 0.4m. Determine the frequency of the waves if the speed of sound in air is 330m/s.
Date posted: May 31, 2019. Answers (1)
- A radio transmitter produces waves of frequency 1.5×108Hz. Determine the wavelength of the signal (C = 3.0 × 108m/s).(Solved)
A radio transmitter produces waves of frequency 1.5×108Hz. Determine the wavelength of the signal (C = 3.0 × 108m/s).
Date posted: May 31, 2019. Answers (1)
- The figure below shows a graph of values of reciprocal of frequency and corresponding values of wavelength for waves transmitted in a certain medium.
i) Using...(Solved)
The figure below shows a graph of values of reciprocal of frequency and corresponding values of wavelength for waves transmitted in a certain medium.
i) Using the wave equation, give the equation of the graph.
ii) Use the graph to determine the velocity of the waves.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a coil connected to a sensitive galvanometer.
When the magnet is suddenly moved towards the coil in the direction shown, the galvanometer...(Solved)
The figure below shows a coil connected to a sensitive galvanometer.
When the magnet is suddenly moved towards the coil in the direction shown, the galvanometer shows a deflection.Explain.
Date posted: May 31, 2019. Answers (1)
- Name an electromagnetic radiation with highest energy photons.(Solved)
Name an electromagnetic radiation with highest energy photons.
Date posted: May 31, 2019. Answers (1)
- An electric heater is rated 1kW, 240V. If the element is connected to 240V mains supply for 10 minutes, determine the amount of heat dissipated.(Solved)
An electric heater is rated 1kW, 240V. If the element is connected to 240V mains supply for 10 minutes, determine the amount of heat dissipated.
Date posted: May 31, 2019. Answers (1)