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If 60% of the Potential Energy Available in a Waterfall is Converted into Heat Energy, Find the Height of the Waterfall, When the Temperature Difference Between the Top and the Bottom of the Fall - Physics

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Question

If 60% of the potential energy available in a waterfall is converted into heat energy, find the height of the waterfall, when the temperature difference between the top and the bottom of the fall is 0.210C (sp. Heat cap. Of water = 4200J/kgK).
Numerical

Solution

Given, Sp. heat capacity of water, s = 4200 J/KgK

Temperature difference, Δt = 0.21 °C

Let 'h' be the height of the waterfall and 'm' be the mass of water.

Then, P.E of the water = mgh

Given that, heat energy, H = 60% of P.E

or, 4200 x 0.21 = 0.6 x 10 x h 

or, h = `(4200 xx 0.21)/(0.6 xx 10) = 882/6` = 147 m

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Chapter 1: Force, Work, Energy and Power - Exercise 5 [Page 60]

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Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 1 Force, Work, Energy and Power
Exercise 5 | Q 7 | Page 60

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