A light beam is described by E=800 sin ω(t-(x/c)) .An electron is allowed to move normal to the propagation of light beam with a speed of 3 × 107 ms -1. What is the maximum magnetic force exerted on the electron ?

Question

A light beam is described by E=800 sin ω(t-(x/c)) .An electron is allowed to move normal to the propagation of light beam with a speed of 3 × 107 ms -1. What is the maximum magnetic force exerted on the electron ? (A) 1.28 × 10-18 N (B) 1.28 × 10-21 N (C) 12.8 × 10-17 N (D) 12.8 × 10-18 N

Tardigrade Admin · Accepted Answer

( E 0/ C )= B 0 F max = eB 0 V =1.6 × 10-19 × (800/3 × 108) × 3 × 107 =12.8 × 10-18 N

Q. A light beam is described by $E = 800 sin ω (t - \frac{x}{c})$ .An electron is allowed to move normal to the propagation of light beam with a speed of $3 \times 1 0^{7} m s^{- 1}$ . What is the maximum magnetic force exerted on the electron ?

$1.28 \times 1 0^{- 18} N$

$1.28 \times 1 0^{- 21} N$

$12.8 \times 1 0^{- 17} N$

$12.8 \times 1 0^{- 18} N$

$\frac{E _{0}}{C} = B_{0}$
$F_{m a x} = e B_{0} V$
$= 1.6 \times 1 0^{- 19} \times \frac{800}{3 \times 1 0 ^{8}} \times 3 \times 1 0^{7}$
$= 12.8 \times 1 0^{- 18} N$

Q. A light beam is described by E=800sinω(t−cx​) .An electron is allowed to move normal to the propagation of light beam with a speed of 3×107ms−1. What is the maximum magnetic force exerted on the electron ?

1.28×10−18N

1.28×10−21N

12.8×10−17N

12.8×10−18N