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A substance of mass M kg requires a powe...

A substance of mass M kg requires a power input of P wants to remain in the molten state at its melting point. When the power source is turned off, the sample completely solidifies in time t seconds. The latent heat of fusion of the substance is …….

A

Pm/t

B

Pt/m

C

m/Pt

D

t/mc

Text Solution

Verified by Experts

The correct Answer is:
B
Heat lost in t second = mL
or heat lost per second = `(mL)/t`
This must be the heat supplied for keeping the substance in matter state per second
`therefore` `(mL)/t = P` or `(Pt)/m`
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Knowledge Check

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