A long straight wire carries a certain current and produces

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A long straight wire carries a certain current and produces a magnetic field of
2 × 10^–4 = weber
m²

at a perpendicular distance of 5 cm from the wire. An electron situated at 5 cm from the wire moves with a velocity 10⁷ m/s towards the wire along perpendicular to it. The force experienced by the electron will be
(charge on electron =1.6 × 10^–19 C)

1. Zero
2. 3.2 N
3. 3.2 × 10^–16 N
4. 1.6 × 10^–16 N

Correct Option: C

Given: Magnetic field B = 2 × 10^–4 weber/m²
Velocity of electron, v = 10⁷ m/s
Lorentz force F = qvB sin θ
= 1.6 × 10^–19 × 10⁷ × 2 × 10^–4 (∵ θ = 90°)
= 3.2 × 10^–16 N

2 × 10^–4 =	weber
	m²