JEE Main2003PhysicsAlternating CurrentActual
A metal wire of linear mass density of 9.8 ~g / m is stretched with a tension of 10 ~kg -wt between two rigid supports 1 metre apart. The wire passes at its middle point between the poles of a permanent magnet, and it vibrates in resonance when carrying an alternating current of frequency n . The frequency n of the alternating source is
Options
- A50 ~Hz
- B100 ~Hz
- C200 ~Hz
- D25 ~Hz
Correct answer
A. 50 ~Hz
Step-by-step solution
n= 1 2 l T ; I=1 m T =10 Kg wt. =10 10=100 ~N =9.8 ~g / m =9.8 10⁻³ ~kg / m n =50 hz