Question
The following phenomenon cannot be observed for sound waves
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Reason : Charges in a conductor reside only at its surface
| Measurement condition | Main scale reading | Circular scale reading |
| Two arms of gauge touching each other without wire | $0$ division | $4$ division |
| Attempt-$1$: With wire | $4$ division | $20$ division |
| Attempt-$2$: With wire | $4$ division | $16$ division |
What are the diameter and cross-sectional area of the wire measured using the screw gauge?