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Asked in NEET 2006 · Work done by friction
Given: W=300 J supplied, m=2 kg, h=10 m, g=10 m s⁻², and the block is slid up (no kinetic energy left over).
Idea: the work supplied goes partly into lifting the block and the rest into friction.
Potential energy gained =mgh=2×10×10=200 J.
W_supplied=Δ U+W_friction.
W_friction=300-200=100 J.
Notice the length of the incline never enters; only the height matters for the lift.
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