An electric motor has an input power of 900 W . The motor takes 1.0 minute to lift a load of weight 240 N at constant speed through a vertical height of 150 m . Resistive forces are negligible. (i) Show that the work done by the motor on the load in 1.0 minute is 36 kJ . efficiency = ..................................................... (iv) Some of the power wasted in the motor is dissipated by the resistance of its coil. This dissipated power is 280 W . The coil of the motor is made from wire of total length 23 m . The wire has a cross- sectional area of $$\(2.6 \times 10^{-8} \mathrm{~m}^{2}\)$$ and is made from metal of resistivity $$\(1.7 \times 10^{-8} \Omega \mathrm{~m}\)$$. Calculate the current in the coil. current $$\(=\)$$ ................................................... A 10

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