Rotational MotionHard
Question
A rod of mass ′m′ is suspended vertically from a hinge A and is free to rotate along a horizontal axis passing through A as shown. A ball of mass m moving horizontally with speed u hits the bottom of the vertical rod elastically at t = 0 sec. Then the linear momentum of the ball and rod system after the collision
Options
A.is same as before the collision
B.becomes lesser than before collision
C.becomes more than before the collision
D.no inference can be drawn
Solution
After collision end of the rod which is at hinge A try to move left so hinge provide force to the rod towards right.
Proof:
Conservation of angular momentum: let U′ is final velocity of block.
mul = m u′l + Iω
Conservation of energy
1/2 mu2 = 1/2 mu′2 + 1/2 Iω2
solving these equation:
We get Lω = 3/2 V
Vcom = 3/4V
V′ = V/2
∴ net linear momentum of the system will be :
3/4MV + MV/2 = 5MV/4
Thus linear momentum will increase
Create a free account to view solution
View Solution FreeMore Rotational Motion Questions
An ant is sitting at the edge of a rotating disc. If the ant reaches the other end, after moving along the diameter, the...A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy (Kt) as well as rot...A particle performs uniform circular motion with an angular momentum L. If the frequency of particle′s motion is d...A ring of diameter 1 metre is rotating with angular momentum of 10 J-s. For increasing its angular momentum by 50% in on...A force of acts on O, the origin of the coordinate system. The torque about the point (1, - 1) is...