Question
A rod of length 1m and mass 0.8kg is lying on a horizontal table. To make it vertical, how much work is required?
Solution
Given,
Length of the rod, l = 1 m
Mass, m = 0.8 kg
When the rod is made vertical from horizontal position, the centre of mass of the rod goes up through height half the length of rod i.e. 0.5m.
Therefore increase in the potential energy of rod is,
This increase in the potential energy is at the cost of work done on the rod.
Thus, work done is,
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Length of the rod, l = 1 m
Mass, m = 0.8 kg
When the rod is made vertical from horizontal position, the centre of mass of the rod goes up through height half the length of rod i.e. 0.5m.
Therefore increase in the potential energy of rod is,
This increase in the potential energy is at the cost of work done on the rod.
Thus, work done is,
