BdPhO Regional (Dhaka-South) Secondary 2019/2

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SINAN EXPERT
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BdPhO Regional (Dhaka-South) Secondary 2019/2

Unread post by SINAN EXPERT » Mon Jan 28, 2019 4:02 pm

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A solid object of mass $4 kg$ is heated at a constant rate $50 W$. The object is kept inside a thermally isolated container so that it cannot radiate heat to the environment. The temperature vs time graph is given. What is the specific latent heat of fusion of the material?
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Re: BdPhO Regional (Dhaka-South) Secondary 2019/2

Unread post by SINAN EXPERT » Fri Feb 01, 2019 6:52 pm

Here, time $ =(50-30) s = 20 s$
So, Heat $=(50*20) = 1000 J$
So, the specific latent heat of the fusion $= \dfrac{1000}{4}=\boxed {250}$ $Jkg^{-1}$
$The$ $only$ $way$ $to$ $learn$ $mathematics$ $is$ $to$ $do$ $mathematics$. $-$ $PAUL$ $HALMOS$

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