Question 1

Paper 2Easy6 marks

An electric winch raises a crate vertically at constant speed. Figure 1 shows the power transfers while the winch is operating.

input power, 150 Wuseful output power, 96 Wwinchdissipated power, 54 W
(a)

State the energy form supplied to the winch and the useful energy form gained by the crate.

[2]
(b)

Calculate the efficiency of the winch.

[2]
(c)

Calculate the useful energy transferred to the crate in 25 s at the operating conditions shown.

[2]

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