Neha keeps the coil exactly the same as in Activity 4.4 but slides the iron nail out, leaving only the coiled wire. Will the coil still deflect the compass? If yes, will the deflection be more or less than before?
Yes, the coil will still deflect the compass because the current carrying coil produces a magnetic field even without the iron nail.
However, the deflection will be less than before because the iron nail acts as a core that strengthens the magnetic field of the electromagnet.
Without the iron core, the electromagnet becomes weaker.
Explanation
The chapter explains in Activity 4.3 that when an iron nail is inserted in the core of the coil, the coil becomes a stronger magnet and the deflection of the magnetic compass needle is much more. For practical applications, most electromagnets have an iron core to make them stronger. Removing the iron nail reduces the strength of the electromagnet.
Solution Steps
The current carrying coil produces a magnetic field even without the iron nail, so the compass will still be deflected.
The iron nail acts as a core that strengthens the magnetic field of the electromagnet.
Without the iron core, the electromagnet becomes weaker, resulting in less deflection than before.