Since the center of mass of the rod is located in the middle, we can express the work of lifting it vertically by the formula:
A = F * h / 2, where F = Ft = m * g (m is the mass of the rod (m = 100 kg), g is the acceleration of gravity (we take g = 9.8 m / s ^ 2), h is the height rod (h = 4 m).
Let’s calculate the value of the work:
A = F * h / 2 = m * g * h / 2 = 100 * 9.8 * 4/2 = 1960 J.
Answer: Work needs to be done in 1960 by J.
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