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What is the power of an engine which can...

What is the power of an engine which can lift 20 metric ton of coal per hour from a mine 30 metres deep ?

Text Solution

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Mass, m = 20 metric ton `= 20xx1000` kg.
Height, h = 30 metres,
Time, t = 1 hour `= 60xx60 sec. 3600` sec.
Power, `("work done")/("time taken")=(mgh)/(t)=((20xx1000)xx(9.8)xx(30))/(3600)`
`=1633.3 W = 1.63 kW`.
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