JEE Advanced 2008Paper 2
- Exam
- JEE Advanced
- Year
- 2008
- Paper
- Paper 2
- Subject
- Physics
- Chapter
- Oscillations
JEE Advanced 2008 · Paper 2 · Physics · Oscillations
Paragraph: A uniform thin cylindrical disk of mass M and radius R...
Paragraph:
A uniform thin cylindrical disk of mass and radius is attached to two identical massless springs of spring constant 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 from its centre. The axle is massless and both the springs and the axle are in a horizontal plane. The unstretched length of each spring is . The disk is initially at its equilibrium position with its centre of mass at a distance Lfrom the wall. The disk rolls without slipping with velocity The coefficient of friction is .
Question: The net external force acting on the disk when its centre of mass is at displacement with respect to its equilibrium position is
Question: The net external force acting on the disk when its centre of mass is at displacement with respect to its equilibrium position is
Options
- A
- B
- C
- D
Correct answer
D.
Step-by-step solution
\left[\frac{f \cdot R}{\frac{1}{2}M R^2}\right]
Solving this equation, we get \frac{2 k x}{3}
\therefore\left|F_{\text{net }}\right|=2 k x-f=2 k x-\frac{2 k x}{3}=\frac{4 k x}{3}
This is opposite to displacement.
\therefore \quad F_{\text{net }}=-\frac{4 k x}{3}
correct option is (d).