NEET2013PhysicsCurrent ElectricityActual
At room temperature, copper has free electron density of 8.4 10²⁸ ~m ⁻³ . The electron drift velocity in a copper conductor of cross-sectional area of 10⁻⁶ ~m ^2 and carrying a current of 5.4 A , will be
Options
- A4 ~ms ⁻¹
- B0.4 ~ms ⁻¹
- C4 ~cm ~s ⁻¹
- D0.4 ~mm ~s ⁻¹
Correct answer
D. 0.4 ~mm ~s ⁻¹
Step-by-step solution
Drift velocity in a copper conductor aligned v_d= i n e A & = 5.4 8.4 10²⁸ 1.6 10⁻¹⁹ 10⁻⁶ & =0.4 10⁻³ ~ms ⁻¹ & =0.4 mms ⁻¹ aligned