Read the Assertion (A) and Reason (R) about a copper wire whose cross-section tapers steadily from 2 mm² at one end to 1 mm² at the other end, carrying a steady current. Choose the correct option.

Assertion (A): The drift speed of the free electrons at the 1 mm² end is twice their drift speed at the 2 mm² end.
Reason (R): In steady state the same current I crosses every cross-section of the wire, and I = neAv_d with the free-electron density n the same throughout the copper.

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Read the Assertion (A) and Reason (R) about a copper wire whose cross-section tapers steadily from 2 mm² at one end to 1 mm² at the other end, carrying a steady current. Choose the correct option.

More NEET Physics chapters

Practising is step one. Knowing what to practise next is the hard part.

Practising is step one. Knowing what to practise next is the hard part