NEET2020Physics-Current Electricity
NEET 2020 Physics Drift Velocity and Mobility MCQ Question
Type: MCQ-numerical-Easy-Class 12
A charged particle having drift velocity of 7.5 × 10⁻⁴ m s⁻¹ in an electric field of 3 × 10⁻¹⁰ V m⁻¹, has a mobility in m² V⁻¹ s⁻¹ of :
A
2.5 × 10⁻⁶
B
2.25 × 10⁻¹⁵
C
2.25 × 10¹⁵
D
2.5 × 10⁶
Correct Answer
Option D
Detailed Explanation
Mobility μ = drift velocity / electric field = vd/E = (7.5 × 10⁻⁴)/(3 × 10⁻¹⁰) = 2.5 × 10⁶ m² V⁻¹ s⁻¹. The correct answer is D (2.5 × 10⁶). The original explanation correctly computed 2.5 × 10⁶ but then stated option A (2.5 × 10⁻⁶) was correct.
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