A disc having velocity v_0 and angular speed | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) $1$. The velocity of the point of contact of the disc with the plank is $v_{contact} = v_0 + \omega_0 R$ in the forward direction. Since the plank

Vedclass · Accepted Answer

Angular momentum of the disc about any point on the horizontal surface remains conserved.

Vedclass · Answer

(D) $1$. The velocity of the point of contact of the disc with the plank is $v_{contact} = v_0 + \omega_0 R$ in the forward direction. Since the plank is initially at rest,there is relative motion,and kinetic friction acts on the disc in the backward direction.$2$. The friction force on the disc is backward,and the reaction force on the plank is forward. Since the external force on the system (disc + plank) in the horizontal direction is zero,the total linear momentum of the system is conserved.$3$. The friction force is kinetic because there is relative slipping between the disc and the plank until pure rolling starts.$4$. The angular momentum of the disc about a point on the horizontal surface is not conserved because the friction force exerts a torque about any point on the horizontal surface (except the point of contact itself,but the question specifies 'any point'). Therefore,option $D$ is incorrect.

$A$ disc having velocity $v_0$ and angular speed $\omega_0$ in the anticlockwise direction is placed on a rough plank. Initially,the plank is at rest. (Assume the length of the plank is very large). Choose the $INCORRECT$ option.

Similar Questions

Which one of the following four graphs best depicts the variation with $x$ of the moment of inertia $I$ of a uniform triangular lamina about an axis parallel to its base at a distance $x$ from it?

The portion $AB$ of the wedge shown in the figure is rough and $BC$ is smooth. $A$ solid cylinder rolls without slipping from $A$ to $B$. The ratio of translational kinetic energy to rotational kinetic energy,when the cylinder reaches point $C$,is:

$A$ solid sphere of mass $M$ and radius $R$ has a moment of inertia $I$ about its diameter. It is recast into a disc of thickness $t$ whose moment of inertia about an axis passing through its edge and perpendicular to its plane remains $I$. The radius of the disc will be:

Vedclass Test Series

Exam Paper Generator

Online Exam Module