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Grade 10General Physics

How to do this. Please help me to answer since my jee exams are near please

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Profile image of Aiswarya
8 Years agoGrade 10
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1 Answer

Profile image of Eshan
8 Years ago
Let the speed of the wedge at that time bev'.

From conservation of linear momentum,

Mv'=mv
\implies v'=\dfrac{mv}{M}

From conservation of energy,

mgh=\dfrac{1}{2}mv^2+\dfrac{1}{2}Mv'^2 =\dfrac{1}{2}mv^2(1+\dfrac{m}{M})

From work energy theorem applied on the block,

Work done by gravity+Work done by normal force=Gain in kinetic energy of the block

\implies mgh+W_N=\dfrac{1}{2}mv^2
\implies W_N=-\dfrac{1}{2}\dfrac{m^2}{M}v^2