Target Exam

CUET

Subject

Physics

Chapter

Current Electricity

Question:

A constant voltage is applied across a wire of non-uniform area of cross-section. Which of the followings quantity is independent of the cross-section?

Options:

Drift speed

Current density

Drift speed and free electron density

Free electron density and the charge crossing per unit time.

Correct Answer:

Drift speed

Explanation:

The correct answer is Option (1) → Drift speed

The Drift speed of electrons is independent of the cross-sectional area of the wire when a constant voltage is applied. It is determined by applied electric field and material properties.