- Sun’s radiation easily passes through the earth’s atmosphere.
- As it warms up, the earth re-radiates energy of longer wavelength (lower energy/
shorter frequency) which is absorbed by water vapour, CO2 and other gases.
- The warm atmosphere in turn radiates back to the earth so making it warmer than
it would otherwise be.
Kavungya answered the question on June 4, 2019 at 07:29
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The bicycle pump shown in Figure below is one of the applications of pressure in
gases.
Explain how the leather washer functions during;
(a) backstroke
(b) forward stroke
(Solved)
The bicycle pump shown in Figure below is one of the applications of pressure in
gases.
Explain how the leather washer functions during;
(a) backstroke
(b) forward stroke
Date posted:
June 4, 2019
.
Answers (1)
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The diagram below shows a spiral spring when not compressed and when
compressed by a mass of 4.0kg.
Determine the elastic potential energy stored by the compressed...
(Solved)
The diagram below shows a spiral spring when not compressed and when
compressed by a mass of 4.0kg.
Determine the elastic potential energy stored by the compressed spring in (b).
Date posted:
June 4, 2019
.
Answers (1)
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A smooth wooden plane is inclined at an angle of 300 to the horizontal as shown in Figure 5 below. An object of mass 10kg...
(Solved)
A smooth wooden plane is inclined at an angle of 300 to the horizontal as shown in Figure 5 below. An object of mass 10kg is pulled steadily up the plane by a force of 60N. Determine;
(a) the velocity ratio of the inclined plane.
(b) efficiency of the system.
Date posted:
June 4, 2019
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Answers (1)
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The figure below shows a rubber bladder filled with air and fixed at the bottom of a
water container and held with a cotton string.
State and...
(Solved)
The figure below shows a rubber bladder filled with air and fixed at the bottom of a
water container and held with a cotton string.
State and explain the observation made when water is heated gently for a few
minutes.
Date posted:
June 4, 2019
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Answers (1)
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An immersion heater consumes a voltage of 240V and a current of 10A. If it is used to heat 5kg of water at 200C, find...
(Solved)
An immersion heater consumes a voltage of 240V and a current of 10A. If it is used to heat 5kg of water at 200C, find the final temperature of water after 7 minutes. (Take the specific heat capacity of water = 4200 J/kgk)
Date posted:
June 4, 2019
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Answers (1)
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A student observed some pollen grains on the surface of water in a beaker with the
help of hand lens as shown below.
(a) State the observation...
(Solved)
A student observed some pollen grains on the surface of water in a beaker with the
help of hand lens as shown below.
(a) State the observation made.
(b) Explain the observation in (a) above.
(c) What conclusion can be drawn from the above experiment.
Date posted:
June 4, 2019
.
Answers (1)
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The figure below shows a force of 40N acting on a body of mass 4kg. The coefficient of friction between the surfaces is 0.05.
Determine the...
(Solved)
The figure below shows a force of 40N acting on a body of mass 4kg. The coefficient of friction between the surfaces is 0.05.
Determine the acceleration of the body.
Date posted:
June 4, 2019
.
Answers (1)
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Define a free fall.
(Solved)
Define a free fall.
Date posted:
June 4, 2019
.
Answers (1)
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The figure below shows a ray of light incident at an angle of 35.60 at point D on the first face of a glass prism...
(Solved)
The figure below shows a ray of light incident at an angle of 35.60 at point D on the first face of a glass prism ABC. The refractive index of the prism is 1.6.
(i) Determine the angle of refraction at point D.
(ii) Find the angle of incidence of the refracted ray on the face AC to 1 decimal point.
(iii) Complete the ray diagram to show the emergent ray from the face AC.
(iv) State two conditions necessary for total internal reflection to occur.
Date posted:
June 3, 2019
.
Answers (1)
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A heater is rated 2000W is used to heat water for 5 hours. Calculate the cost of electricity at Ksh.6.70 per unit.
(Solved)
A heater is rated 2000W is used to heat water for 5 hours. Calculate the cost of electricity at Ksh.6.70 per unit.
Date posted:
June 3, 2019
.
Answers (1)
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An object of height 10.5cm stands before a diverging lens of focal length 20cm and a distance of 10cm from the lens. Determine;
(i) image distance....
(Solved)
An object of height 10.5cm stands before a diverging lens of focal length 20cm and a distance of 10cm from the lens. Determine;
(i) image distance.
(ii) height of the image.
(iii) magnification.
Date posted:
June 3, 2019
.
Answers (1)
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The graph below show stopping potential Vs against frequency f. (Take C = 3.0 x 108ms¯¹).
Use the graph to determine:-
(i) the threshold wavelength.
(ii) Planck’s...
(Solved)
The graph below show stopping potential Vs against frequency f. (Take C = 3.0 x 108msˉ¹).
Use the graph to determine:-
(i) the threshold wavelength.
(ii) Planck’s constant.
(iii) the work function of the metal.
Date posted:
June 3, 2019
.
Answers (1)
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Four capacitor are connected as shown.
Calculate the effective capacitance between A and B.
(Solved)
Four capacitor are connected as shown.
Calculate the effective capacitance between A and B.
Date posted:
June 3, 2019
.
Answers (1)
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Sketch a circuit diagram to show how two diodes can be used as a current full wave rectifier.
(Solved)
Sketch a circuit diagram to show how two diodes can be used as a current full wave rectifier.
Date posted:
June 3, 2019
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Answers (1)
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What is the voltage output for the cell arrangement below?
(Solved)
What is the voltage output for the cell arrangement below?
Date posted:
June 3, 2019
.
Answers (1)
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The figure below shows a uniform rod of height 8cm floating vertically in a beaker containing two immiscible liquids P and Q. The densities of...
(Solved)
The figure below shows a uniform rod of height 8cm floating vertically in a beaker containing two immiscible liquids P and Q. The densities of the liquids are 800kg/m³ and 1200g/m³ respectively the cross-sectional area of the rod is 2cm².
Determine
(i) the weight of liquid P displaced by the rod.
(ii) the weight of liquid Q displaced by the rod.
(iii) the mass of the rod.
(iv) the density of the rod.
Date posted:
June 3, 2019
.
Answers (1)
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A car of mass 1200kg is negotiating a curve of radius 45m on a horizontal road. The force of friction between the tyres and the...
(Solved)
A car of mass 1200kg is negotiating a curve of radius 45m on a horizontal road. The force of friction between the tyres and the road is 6700N. Determine the maximum speed at which the car can be driven on the curve without going off the road.
Date posted:
June 3, 2019
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Answers (1)
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The diagram below shows a simplified hydraulic braking system of a car.
(i) State the property of the liquid (oil) that makes its more suitable than...
(Solved)
The diagram below shows a simplified hydraulic braking system of a car.
(i) State the property of the liquid (oil) that makes its more suitable than a gas for use as a brake fluid.
(ii) Explain how the system works starting from when the driver presses the foot pedal.
Date posted:
June 3, 2019
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Answers (1)
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Explain how a person is able to draw milk from a glass using a straw.
(Solved)
Explain how a person is able to draw milk from a glass using a straw.
Date posted:
June 3, 2019
.
Answers (1)
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The following figure shows a wheel and axle used to raise a load W by applying an effort F. The radius of the larger wheel...
(Solved)
The following figure shows a wheel and axle used to raise a load W by applying an effort F. The radius of the larger wheel is R and the small wheel is y.
Given that v = 5cm and R is 8cm, determine the effort required to raise a load of 20N if the efficiency of the system is 80%.
Date posted:
June 3, 2019
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Answers (1)