NEETPhysicsMagnetic Effects of Current
STATEMENT - 1 A loosely bound helix made of stiff wire is suspended vertically with the lower end just touching a dish of mercury. When a current is passed though the wire, the wire executes oscillatory motion with the lower end jumping out of and into the mercury. STATEMENT - 2 When electric current is passed through helix, a magnetic field is produced both inside and outside the helix.
Options
- AStatement - 1 is True, Statement - 2 is True; Statement - 2 is a correct explanation for Statement - 1.
- BStatement - 1 is True, Statement - 2 is True; Statement - 2 is NOT a correct explanation for Statement - 1.
- CStatement - 1 is True, Statement - 2 is False.
- DStatement - 1 is False, Statement - 2 is True.
Correct answer
B. Statement - 1 is True, Statement - 2 is True; Statement - 2 is NOT a correct explanation for Statement - 1.
Step-by-step solution
The winding of helix carry currents in same direction. Hence they experience an attractive force pulling the lower and out of mercury. As a result of this the circuit breaks and so the force of attraction vanishes and the helix comes back to its initial position, completing the circuit again.