Get premium membership and access questions with answers, video lessons as well as revision papers.
- A stone of mass 40g is tied to the end of a string 50cm long such that it is 20m above the ground at its...(Solved)
A stone of mass 40g is tied to the end of a string 50cm long such that it is 20m above the ground at its lowest level as shown in the diagram below. It is whirled in a vertical circle at 2rev/s.
(i) If the string breaks at its lowest level as shown, what is the velocity with which it travels?
Calculate the maximum tension in the string.
(ii) Calculate the maximum tension in the string.
(iii) Determine the maximum horizontal distance it travels from the breaking point
Date posted: September 6, 2019. Answers (1)
- Using Kinetic theory of matter, explain why solids expand when heated.(Solved)
Using Kinetic theory of matter, explain why solids expand when heated.
Date posted: September 6, 2019. Answers (1)
- The figure below shows a machine being used to raise a load.Determine the efficiency of the machine.(Solved)
The figure below shows a machine being used to raise a load.Determine the efficiency of the machine.
Date posted: September 6, 2019. Answers (1)
- The diagram below shows a braking system.Why is the master piston, made smaller than the slave piston?(Solved)
The diagram below shows a braking system.Why is the master piston, made smaller than the slave piston?
Date posted: September 6, 2019. Answers (1)
- The diagram below shows a uniform 5m long metal rod of mass 800g. It is suspended by a string tied at a point 3.5m from...(Solved)
The diagram below shows a uniform 5m long metal rod of mass 800g. It is suspended by a string tied at a point 3.5m from one end. Determine the load which should be hung at point X to keep the plank horizontal.
Date posted: September 6, 2019. Answers (1)
- A tube of radius 9 mm has a constriction of diameter 10mm. Water flows in the tube at 3m/s. Determine the velocity of water in...(Solved)
A tube of radius 9 mm has a constriction of diameter 10mm. Water flows in the tube at 3m/s. Determine the velocity of water in the constriction.
Date posted: September 6, 2019. Answers (1)
- The diagram below shows a micrometer screw gauge. What is the reading in SI units?(Solved)
The diagram below shows a micrometer screw gauge. What is the reading in SI units?
Date posted: September 6, 2019. Answers (1)
- A cell supplies a current of 0.5A when connected to a 2 ohms resistor and 0.25A when connected to a 5 ohms resistor. Find the...(Solved)
A cell supplies a current of 0.5A when connected to a 2 ohms resistor and 0.25A when connected to a 5 ohms resistor. Find the e.m.f and the internal resistance of the cell.
Date posted: September 6, 2019. Answers (1)
- The figure shows three resistors as shown.If the voltmeter reads 4V, find the(Solved)
The figure shows three resistors as shown.If the voltmeter reads 4V, find the
(i) Effective resistance
(ii) Current through the 3 ohms resistor
(iii) Potential difference across the 8 ohms resistor.
Date posted: September 6, 2019. Answers (1)
- Define electric resistance.(Solved)
Define electric resistance.
Date posted: September 6, 2019. Answers (1)
- Light of frequency 5.50 x 1014 Hz is incident on a surface whose work function is 2.5ev.
(i) Determine the energy of photons of light in...(Solved)
Light of frequency 5.50 x 1014 Hz is incident on a surface whose work function is 2.5ev.
(i) Determine the energy of photons of light in eV. (Take h = 6.63 x 10-34 Js) and 1eV
(ii) Will photoelectric emission occur? Explain
Date posted: September 6, 2019. Answers (1)
- The figure below shows photocell used in a set-up for a burglar alarm.(Solved)
The figure below shows photocell used in a set-up for a burglar alarm.
(i) Give a reason why the photocell is usually evacuated.
(ii) State the function of the resistor R in this circuit
(iii) Explain why a particular radiation such as ultra-violet light is used to strike a given cathode surface.
(iv) Explain how the set-up in the figure can be used as a burglar alarm.
Date posted: September 6, 2019. Answers (1)
- The figure below illustrates a method of charging a metal sphere.(Solved)
The figure below illustrates a method of charging a metal sphere.
(i) Name the method of charging shown in the figure.
(ii) Indicate the final charge on the sphere in the figure.
Date posted: September 6, 2019. Answers (1)
- In an experiment to investigate factors affecting capacitance of a capacitor, a student increased the area of the plates and decreased the separation of the...(Solved)
In an experiment to investigate factors affecting capacitance of a capacitor, a student increased the area of the plates and decreased the separation of the plates. Explain the effect on the capacitance when
(i) the area of plates increased
(ii) the distance of the separation of the plates decreased
Date posted: September 6, 2019. Answers (1)
- A converging lens forms an image which is three times the object. Determine the focal length of the lens if the distance between the object...(Solved)
A converging lens forms an image which is three times the object. Determine the focal length of the lens if the distance between the object and the screen is 80cm.
Date posted: September 6, 2019. Answers (1)
- The graph below shows the variation of 1/v and 1/u in an experiment to determine the focal length of a lens.(Solved)
The graph below shows the variation of 1/v and 1/u in an experiment to determine the focal length of a lens.
(i) Use the graph to determine the focal length
(ii) What is the power of the lens used?
Date posted: September 6, 2019. Answers (1)
- An optician in Eldoret Hospital examined an eye of a patient and made the following observations:
Eye too short and the focal length of the eye...(Solved)
An optician in Eldoret Hospital examined an eye of a patient and made the following observations:
Eye too short and the focal length of the eye lens short
(i) State the eye defect the patient could be having.
(ii) Use a diagram to describe how the defect could be corrected.
Date posted: September 6, 2019. Answers (1)
- Some students wish to determine the focal length of a convex lens of thickness 0.6cm using an optical pin and a plane mirror.The figure shows...(Solved)
Some students wish to determine the focal length of a convex lens of thickness 0.6cm using an optical pin and a plane mirror.The figure shows the experimental set up when there is no parallax between the pin and the image.
Determine the focal length of the lens.
Date posted: September 6, 2019. Answers (1)
- Below is part of a circuit that was setup by form four students of Okok Seconday School during a physics practical lesson to demonstrate full...(Solved)
Below is part of a circuit that was setup by form four students of Okok Seconday School during a physics practical lesson to demonstrate full wave rectification using two diodes. Complete the circuit by correctly placing the load R and two diodes.
Date posted: September 6, 2019. Answers (1)
- A sample of a radioactive substance initially has 8.0 x 1025 particles. The half life of the sample is 98 seconds. Determine the number of...(Solved)
A sample of a radioactive substance initially has 8.0 x 1025 particles. The half life of the sample is 98 seconds. Determine the number of particles that will remain after 294 seconds.
Date posted: September 6, 2019. Answers (1)