1. Tardigrade
  2. Question
  3. Physics
  4. A uniform thin cylindrical disk of mass M and radius R is attached to two identical massless springs of spring constant k which are fixed to the wall as shown in the figure. The springs are attached to the axle of the disk symmetrically on either side at a distance d from its centre. The axle is massless and both the springs and the axle are in horizontal plane. The unstretched length of each spring is L. The disk is initially at its equilibrium position with its centre of mass (CM) at a distance L from the wall. The disk rolls without slipping with velocity V 0= V 0 hat i . The coefficient of friction is μ . <img class=img-fluid question-image alt=image src=https://cdn.tardigrade.in/img/question/physics/7d7640f39f5913e9c688e0b549b1f509-.png /> The net external force acting on the disk when its centre of mass is at displacement x with respect to its equilibrium position is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A uniform thin cylindrical disk of mass $M$ and radius $R$ is attached to two identical massless springs of spring constant $k$ which are fixed to the wall as shown in the figure. The springs are attached to the axle of the disk symmetrically on either side at a distance $d$ from its centre. The axle is massless and both the springs and the axle are in horizontal plane. The unstretched length of each spring is $L$. The disk is initially at its equilibrium position with its centre of mass $(CM)$ at a distance $L$ from the wall. The disk rolls without slipping with velocity $\overrightarrow{ V }_{0}= V _{0} \hat{ i }$. The coefficient of friction is $\mu .$
image
The net external force acting on the disk when its centre of mass is at displacement $x$ with respect to its equilibrium position is

JEE AdvancedJEE Advanced 2008

Solution:

$2 l x - f = ma$
$\Rightarrow f \cdot R = I \alpha$
$a = R \alpha$
$\Rightarrow ma =\frac{4 kx }{3}$