Efficiency = $\frac{M.A}{V.R}$ x 100
$\frac{100}{20}$ x $\frac{1}{4}$ x 100
= 89.3%
johnmulu answered the question on February 14, 2017 at 12:30
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A body of mass M is allowed to slide down an inclined plane. State two factors that affects its final velocity at the bottom of the incline.
(Solved)
A body of mass M is allowed to slide down an inclined plane. State two factors that affects its final velocity at the bottom of the incline.
Date posted:
February 14, 2017
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Answers (1)
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Date posted:
February 14, 2017
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Answers (1)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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A trolley is moving at a uniform speed along a track. A piece of plasticine is dropped on the trolley and sticks on it. Explain why the trolley slows down
(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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A high jumper usually lands on thick soft mattress. Explain how the mattress helps in reducing the force of impact
(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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An industrial trolley of mass 20 kg carrying a mass of 50 kg is acted on by a constant force. The trolley moves along a horizontal smooth surface with an acceleration of 0.5ms-2
(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
A gun is fired vertically upwards from the top of an open truck moving horizontally, uniform velocity of 50ms-1. The bullet achieves a maximum height of 45 m.
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Date posted:
February 14, 2017
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Answers (1)
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A trolley is moving at constant speed in friction compensated track. Some plasticine is dropped on the trolley and sticks on it. State with a reason what is observed about the motion of the trolley.
(Solved)
A trolley is moving at constant speed in friction compensated track. Some plasticine is dropped on the trolley and sticks on it. State with a reason what is observed about the motion of the trolley.
Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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(Solved)
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Date posted:
February 14, 2017
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Answers (1)
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A water wave of wavelength 18 mm is incident on a boundary of shallow water at right angles. If the wavelength in the shallow end is 14.4 mm
(Solved)
A water wave of wavelength 18 mm is incident on a boundary of shallow water at right angles. If the wavelength in the shallow end is 14.4 mm, Determine the refractive index of water for a wave moving from the deep to the shallow end.
Date posted:
February 14, 2017
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Answers (1)
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Determine the speed of light in water given that the speed of light in air is 3.0 x 108 ms-1 and the refractive index of water is 1.33
(Solved)
Determine the speed of light in water given that the speed of light in air is 3.0 x 108 ms-1 and the refractive index of water is 1.33.
Date posted:
February 14, 2017
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Answers (1)
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One of the conditions for total internal reflection to occur is that angle of incidence must be greater than the critical angle of the medium. State the other condition
(Solved)
One of the conditions for total internal reflection to occur is that angle of incidence must be greater than the critical angle of the medium. State the other condition.
Date posted:
February 14, 2017
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Answers (1)
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A small object lies at the bottom of a water pond at a depth of 1.2 m. Given that the refractive index of water is 1.3
(Solved)
A small object lies at the bottom of a water pond at a depth of 1.2 m. Given that the refractive index of water is 1.3, Determine the apparent depth of the object. (Give your to 1 decimal place)
Date posted:
February 14, 2017
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Answers (1)
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Light travels through glass of refractive index 1.5 with a speed V. Calculate the value of V. (Speed of light in air = 3.0 x 108m/s)
(Solved)
Light travels through glass of refractive index 1.5 with a speed V. Calculate the value of V. (Speed of light in air = 3.0 x 108m/s)
Date posted:
February 14, 2017
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Answers (1)