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Photoelectric effect.
sharon kalunda answered the question on March 25, 2019 at 13:14
- Why are people who are maimed or have lost one leg provided with crutches?(Solved)
Why are people who are maimed or have lost one leg provided with crutches?
Date posted: March 25, 2019. Answers (1)
- Give an expression which can be used to calculate electrical energy.(Solved)
Give an expression which can be used to calculate electrical energy.
Date posted: March 25, 2019. Answers (1)
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Why is it very difficult to open a door from a point too close to hinges?
Date posted: March 25, 2019. Answers (1)
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Why is a point source of X-rays needed to produce X-ray shadow photographs?
Date posted: March 25, 2019. Answers (1)
- State the energy changes that occur in the cathode ray tube.(Solved)
State the energy changes that occur in the cathode ray tube.
Date posted: March 25, 2019. Answers (1)
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Sketch a diagram of a simple cell.
Date posted: March 25, 2019. Answers (1)
- The figure shows a device for closing a steam outlet
Determine the weight W that just holds the bar in the horizontal position shown.(Solved)
The figure shows a device for closing a steam outlet
The area of the piston is 4.0 x 10-4 m2 and the pressure of the steam in the boiler
is 2.0 x 105Nm-2. Determine the weight W that just holds the bar in the horizontal
position shown.
Date posted: March 25, 2019. Answers (1)
- A battery rated 80Ah. What does this mean?(Solved)
A battery rated 80Ah. What does this mean?
Date posted: March 25, 2019. Answers (1)
- A power line from a power sub-station to a town a few kilometres away has a resistance of 0.1 Ohm per kilometre. Determine the rate...(Solved)
A power line from a power sub-station to a town a few kilometres away has a resistance of 0.1 Ohm per kilometre. Determine the rate of energy loss is transmission of power over 50km at a current of 60 amperes.
Date posted: March 25, 2019. Answers (1)
- The figure below shows an arrangement for lighting three lamps, A, B and C only one of which is controlled directly by the switch.(Solved)
The figure below shows an arrangement for lighting three lamps, A, B and C only one of which is controlled directly by the switch.
a) Which of he lamp is directly controlled by the switch?
b) What is the name given to this use of an electromagnet?
c) Which lamps can be on at once?
d) Explain how lamp C comes in.
Date posted: March 25, 2019. Answers (1)
- In an experiment, the diameter, of the patch was measured to be 200mm for an oil drop of radius 0.25mm. Determine the diameter of the...(Solved)
In an experiment, the diameter, of the patch was measured to be 200mm for an oil drop of radius 0.25mm. Determine the diameter of the molecule of the oil.
Date posted: March 25, 2019. Answers (1)
- State one application of visible light.(Solved)
State one application of visible light.
Date posted: March 25, 2019. Answers (1)
- Arrange the following waves in order of decreasing wavelength.
Infrared, X-rays, microwaves, yellow light, radio waves, red light.(Solved)
Arrange the following waves in order of decreasing wavelength.
Infrared, X-rays, microwaves, yellow light, radio waves, red light.
Date posted: March 25, 2019. Answers (1)
- Two pins are hanging from a magnet as shown in the diagram below.(Solved)
Two pins are hanging from a magnet as shown in the diagram below.
Explain why they do not hang vertically downwards.
Date posted: March 25, 2019. Answers (1)
- The figure below shows a positive charge near a plate carrying negative charge.(Solved)
The figure below shows a positive charge near a plate carrying negative charge
Draw an electric field pattern between them
Date posted: March 25, 2019. Answers (1)
- A concave mirror produces a real image 2cm tall of an object 5.0mm tall placed 10cm from the mirror. Find the focal length of the...(Solved)
A concave mirror produces a real image 2cm tall of an object 5.0mm tall placed 10cm from the mirror. Find the focal length of the mirror.
Date posted: March 25, 2019. Answers (1)
- The figure below shows a ray of light incident to the first of the two mirrors placed at an angle of 60°.(Solved)
The figure below shows a ray of light incident to the first of the two mirrors placed at an angle of 60°.
Complete the part of the ray after reflection from the mirrors.
Date posted: March 25, 2019. Answers (1)
- A gas of volume 2m³ at 27°C is cooled to -123°C, at constant pressure. What is its new volume?(Solved)
A gas of volume 2m³ at 27°C is cooled to -123°C, at constant pressure. What is its new volume?
Date posted: March 25, 2019. Answers (1)
- A block of length 80cm, cross sectional area 3.0cm² and density 1300kg/m³ is completely immersed in a liquid of density 1030kg/m³. Determine
i) The mass of...(Solved)
A block of length 80cm, cross sectional area 3.0cm² and density 1300kg/m³ is completely immersed in a liquid of density 1030kg/m³. Determine
i) The mass of the block.
ii) The weight of the block in the liquid.
Date posted: March 25, 2019. Answers (1)
- A stone of mass 1.2 kg is tied to a rope and whirled in a vertical circle of radius 3.2m with a speed of 6.32m/s....(Solved)
A stone of mass 1.2 kg is tied to a rope and whirled in a vertical circle of radius 3.2m with a speed of 6.32m/s. Calculate
i) The centripetal acceleration of the stone.
ii) The tension in the rope when the stone is at the highest point.
Date posted: March 25, 2019. Answers (1)