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ID: 2842403 • Letter: #

Question

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Explanation / Answer

V=piR^2h/3

Given h=3/8(2R)

h=3R/4

R=4h/3

So V=pi(16h^2/9)h/3

=16pih^3/27

Dedicating with respect to time we get

dV/dt=16pi/27(3h^2)(dh/dt)

At h=4

15=256pi/9(dH/dt)

dH/dt=225/256pi

=0.2799 m/min

So the rate of increase of height is 0.2799 metres/ min