Rotational MotionHard
Question
A man can move on a horizontal plank supported symmetrically as shown. The variation of normal reaction on support A with distance x of the man from the end of the plank is best represented by


Options
A.

B.

C.

D.

Solution
For the translator & rotatory equilibrium let the normal at point ′A′ & ′B′ be NA & NB
∴ NA + NB = mg (m → mass of man)
& Torque about the centre of plank - NA × 2 + NB × 2 + mg (3 - x) = 0
As x increases (NA ≡ N) decreases.
(NB - NA) × 2 = mg(3 - x)
∴ NA + NB = mg (m → mass of man)
& Torque about the centre of plank - NA × 2 + NB × 2 + mg (3 - x) = 0
As x increases (NA ≡ N) decreases.
(NB - NA) × 2 = mg(3 - x)
Create a free account to view solution
View Solution FreeMore Rotational Motion Questions
A force of acts on O, the origin of the coordinate system. The torque about the point (1, - 1) is...All the particles of a rigid rotating body move in a circular path when the axis of rotation:-...A non uniform rod OA of liner mass density λ = λ0x (λ0 = co nst.) is suspended from ceiling with hinge jo...The radius of a wheel of a car is 0.4m. The car is accelerated from rest by an angular acceleration of 1.5 rad/s2 for 20...A sphere S rolls without slipping, moving with a constant speed on a plank P. The friction between the upper surface of ...