Answer to Question #214435 in Electricity and Magnetism for Muthiah Afifah

Question

Which of the following statements are not true about electric force Fe and magnetic force Fm on a charged particle? (a) E and Fe are parallel to each other, whereas B and Fm are perpendicular to each other. (b) Both Fe and Fm depend on the velocity of the charged particle. (c) Both Fe and Fm can perform work. (d) Both Fe and Fm are produced when a charged particle moves at a constant velocity. (e) Fm is generally small in magnitude in comparison to Fe. (f) Fe is an accelerating force, whereas Fm is a purely deflecting force

Answer 1

Magnetic force

$F_m=qvBsin\theta$

$F_E=qE$

(a) q is moved parralled to magnetic field

$\theta=90°$

$F_m=qvB,sin90°=1$

Option (a) is correct

Part (b)

$F_e$ is does not depend on velocity

But $F_m$ is depend velocity

Option (b) correct

Part(c)

$F_E,F_m$ Both force perform work is correct option

Option (c) is correct

Part(d) $F_e$

Both F_e,F_m are produced when a charge particle move as a constant velocity is wrong

Option (d) is incorrect statement (false)

Part(e)

$F_m$ Generally small in magnitude comperision $F_e$ Correct statement

Option (e) is correct

Part(f)

$F_e$ is an accelerating force, where as $F_m$ is a purely deflecting forceis true statement option (f) correct