A metallic rod of mass per unit length 0.5 kg m-1 is lying horizontally on a smooth inclined plane which makes an angle of 30o with the horizontal. The rod is not allowed to slide down by flowing a current through it when a magnetic field of induction 0.25 T is acting on it in the vertical direction. The current flowing in the rod to keep it stationary is
14.76 A
5.98 A
7.14 A
11.32 A
As we have learned
Force on a current carrying conductor -
- wherein
idl=current element
To keep the rod stationary
or
angle between rod and magnetic field is 90-
i.e
or
Option 1)
14.76 A
This is incorrect
Option 2)
5.98 A
This is incorrect
Option 3)
7.14 A
This is incorrect
Option 4)
11.32 A
This is correct