JEE MATHEMATICS MCQ: RATE MEASURE

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Application +4 | -1

Rays from the sun are focused by a lens of diameter 5m on to a block of ice

\left( {l = 80\,kcal/10g} \right)

and 10 g of ice is melted in 20 minutes. Calculate the heat received from the sun on

1\,c{m^2}

per minute

View answer and explanation

Correct option: D

2 cal

Option D (2 cal) is correct because it is the heat received per unit area per minute, calculated from the latent heat of fusion and the area of the lens.

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