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That the appliance operates at a voltage of 240 volts. When it is operating normally, the electrical power outputs is 200 watts i.e. 200J of electrical energy is converted to other useful energy per unit time
Wilfykil answered the question on March 26, 2019 at 13:29
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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The figure below shows a force distance graph for a car being on a horizontal ground
a) Calculate the total work done
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c) An electric pump can raise water from a lower-level reservoir to the high level reservoir to the high level reservoir at the rate of 3.0 x 105 kg per hour. The vertical height of the water is raised 360m. If the rate of energy loss in form of heat is 200 kW, determine the efficiency of the pump.
Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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A workshop has the following simple machines for lifting heavy loads, a wheel and axle, and a movable pulley. The wheel has a diameter of 30cm while the axle has diameter of 3.0cm.
i) Sketch force diagrams to show how each machine works.
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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Date posted: March 26, 2019. Answers (1)
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A screw advances 1mm when the screw is turned through two revolutions. What is the pitch of the screw?
Date posted: March 26, 2019. Answers (1)
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Suggest two energy changes that accompany the changing of a liquid in a vapour phase.
Date posted: March 26, 2019. Answers (1)
- A pump uses 1g of a mixture of petrol and alcohol in the ratio 4:1 by mass to raise 1000 kg of water from a...(Solved)
A pump uses 1g of a mixture of petrol and alcohol in the ratio 4:1 by mass to raise 1000 kg of water from a well 200m deep.
i) How much energy is given by 1g of mixture?
ii) If the pump is 40% efficient, what mass of this mixture is needed to raise the water? (1g of alcohol = 7000J, of petrol= 48000J)
Date posted: March 26, 2019. Answers (1)
- An energy saving stove when burning steadily has an efficiency of 69%. The stove melts 0.03 kg lf ice 00C in 180 seconds. (Solved)
An energy saving stove when burning steadily has an efficiency of 69%. The stove melts 0.03 kg lf ice 00C in 180 seconds.
Calculate: -
i) The power rating of the stove.
ii) The heat energy wasted by the stove.
Date posted: March 26, 2019. Answers (1)