JEE Advanced2011PhysicsOscillationsActual
A wooden block performs SHM on a frictionless surface with frequency v₀ . The block carries a charge +Q on its surface. If now a uniform electric field E is switched on as shown, then the SHM of the block will be
Options
- Aof the dame frequency and with shifted mean position
- Bof the same frequency and with the same mean position
- Cof changed frequency and with shifted mean position
- Dof changed frequency and with the same mean position
Correct answer
A. of the dame frequency and with shifted mean position
Step-by-step solution
Frequency or time period of SHM depends on variable forces. It does not depend on constant external force. Constant external force can only change the mean position. For example, in the given question mean position is at natural length of spring in the absence of electric field. Whereas in the presence of electric field mean position will be obtained after a compression of x₀ . Where x₀ is given by or aligned k x₀ & =Q E x₀ & = Q E k aligned Correct answer is (a). Analysis of Question (i) Question is simple. (ii) I