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Work Power and Energy question

2021 · 1 Sep · Shift 2 · Q50
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  5. /2021 · 1 Sep · Shift 2 · Q50

Work Power and Energy question

2021 · 1 Sep · Shift 2 · Q50

JEE MainPhysicsWork Power and EnergyMCQ+4 / −1
A body of mass 'm' dropped from a height 'h' reaches the ground with a speed of 0.8 gh\sqrt {gh}gh​. The value of workdone by the air-friction is :
  1. A
    −-− 0.68 mgh
  2. B
    mgh
  3. C
    1.64 mgh
  4. D
    0.64 mgh
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