A meter scale of mass `400 gm` is lying horizontally on the floor. If it is to be held vertically with one end touching the floor, the work to be done isA. `6 J`B. `4 J`C. `40 J`D. `2J`

A meter scale of mass `400 gm` is lying horizontally on the floor. If

1.	A meter scale of mass `400 gm` is lying horizontally on the floor. If it is to be held vertically with one end touching the floor, the work to be done isA. `6 J`B. `4 J`C. `40 J`D. `2J`
Answer» Correct Answer - D `W = vec(F).vec(S) = FS_("com")` , where `F = mg` and `S_("com") = (L)/(2)`

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A meter scale of mass `400 gm` is lying horizontally on the floor. If it is to be held vertically with one end touching the floor, the work to be done isA. `6 J`B. `4 J`C. `40 J`D. `2J`

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