(i) work done = Area under the graph
= (40x20) + (20 x 10) = (80 x 40)
= 800 + 200 + 3200 = 4200J
(ii) work done = mgh
= 25 x 10 x 12 = 3000J
Energy wasted = (4200 – 3000)J = 1200J
(iii) Friction force between the surfaces. Some work is done against friction
sharon kalunda answered the question on April 2, 2019 at 11:15
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Figure below shows a wire loop with a string that has been dipped into soap solution.
(Solved)
Figure below shows a wire loop with a string that has been dipped into soap solution.
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April 2, 2019
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April 2, 2019
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April 2, 2019
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April 2, 2019
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April 2, 2019
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Date posted:
April 2, 2019
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Answers (1)
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April 2, 2019
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Date posted:
April 2, 2019
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Answers (1)
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Calculate the diameter of the...
(Solved)
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Date posted:
April 2, 2019
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Answers (1)
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A crane lifts a load 500kg through a vertical distance of 4m in 8 seconds. Determine:
(Solved)
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April 2, 2019
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Answers (1)
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Date posted:
April 2, 2019
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Answers (1)
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Date posted:
April 2, 2019
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Answers (1)
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A bicycle has wheels 66 cm in diameter. Its crank wheel has 44 teeth and the rear sprocket 16 teeth. The crank radius is 16.5...
(Solved)
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Date posted:
April 2, 2019
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Answers (1)
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A wheel and axle are used to raise a load of 280N by a force 40N applied to the rim of the
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(Solved)
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Date posted:
April 2, 2019
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Answers (1)
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The graph below shows the potential energy against displacement for a body of mass 80 g.
(Solved)
The graph below shows the potential energy against displacement for a body of mass 80 g.
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Date posted:
April 2, 2019
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Answers (1)
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(Solved)
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Date posted:
April 2, 2019
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Answers (1)
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(Solved)
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Date posted:
April 2, 2019
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Answers (1)
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Briefly explain two ways other than direct heating by which quantity of liquid may be made to evaporate more quickly
(Solved)
Briefly explain two ways other than direct heating by which quantity of liquid may be made to evaporate more quickly
Date posted:
April 2, 2019
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Answers (1)
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0.5kg of naphthalene contained in an aluminium can of mass 0.4kg is melted in a water bath and raised to a temperature of 100oC ....
(Solved)
0.5kg of naphthalene contained in an aluminium can of mass 0.4kg is melted in a water bath and raised to a temperature of 100oC . Calculate the total heat given out when the can and its contents are allowed to cool to room temperature, 20oC . Neglect losses by evaporation during heating process and give your answer to the nearest kilojoule.(For naphthalene melting point = 80oC , Specific heat capacity for both liquid and solid =2100J/KgK; specific latent heat of fusion = 170000J/Kg.For aluminium: specific heat capacity = 900J/Kg/k
Date posted:
April 2, 2019
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Answers (1)
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An electric heater 1KW 240V is used to raise the temperature of a 5kg copper block from 15oC to 33oC. If the specific heat capacity...
(Solved)
An electric heater 1KW 240V is used to raise the temperature of a 5kg copper block from 15oC to 33oC. If the specific heat capacity of copper is 400J/Kg/K and assuming no heat is lost to the surrounding,Calculate the time taken.
Date posted:
April 2, 2019
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Answers (1)