NEETPhysicsRotational MotionMCQ+4 / −1
A rod of weight W is supported by two parallel knife edges A and B and is in equilibrium in a horizontal position. The knives are at a distance d from each other. The centre of mass of the rod is at distance x from A. The normal reaction on A is
- A
- B
- C
- D
View written solutionFree
Correct answer: B

Given situation is shown in figure.
N1 = Normal reaction on A
N2 = Normal reaction on B
W = Weight of the rod
In vertical equilibrium,
N1 + N2 = W …(i)
Torque balance about centre of mass of the rod,
N1x = N2(d – x)
Putting value of N2 from equation (i)
N1x = (W – N1)(d – x)
N1x = Wd – Wx – N1d + N1x
N1d = W(d – x)
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