# physics

a boy weighing 350N runs up a flight of stairs consisting of 20 steps each 10cm high in 10 seconds. What is his power? show your workings

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3. 👁 1,640
1. The height is
h = 20•0.1 = 2 m
The work is W = mgh =350•2 = 700 J
Power = Work/time = 700/10 =70 W

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2. A 40kilowatt electric cable ??\$ used to transmit electricity through a resistor of resistance 2ohms at 800 volts, the power loss at energy is? Pls show workings

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3. A generator ??\$ on daily use in the process 106kw ????? 540w tungsten box are on force the same time interval. Thee energy consumed is

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4. a person with a mass of 40 kg runs up a flight of stairs in 12 seconds the flight has 20 steps and the height of each step is 20cm

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5. 133.33 W

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6. 13.33 W

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