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Height of water dam in hydroelectric pow...

Height of water dam in hydroelectric power station is 20m. How much water, in 1 second, should fall on turbine, so that 1 MW power is generated? `(g=10ms^(-2))`

A

`5000kg`

B

`10,000kg`

C

`500kg`

D

`7500kg`

Text Solution

Verified by Experts

The correct Answer is:
A
`h=20m,P=1MW=10^(6)W,t=1s`,
`g=10ms^(-2)`
`therefore P=(W)/(t)=(mgh)/(t)`
`therefore m=(Pxxt)/(gxxh)=(10^(6)xx1)/(10xx20)=5000kg`
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KUMAR PRAKASHAN-WORK AND ENERGY -QUESTION & ANSWER (CHOOSE THE CORRECT OPTION FROM THOSE GIVEN BELOW EACH QUESTION)
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