The magnetic field of an EM wave travelling along X-axis is vector B

1.	The magnetic field of an EM wave travelling along X-axis is vector B = k [4 × 10-4 sin (ωt – kx)]. Here B is in tesla, t is in second and x is in m. Calculate the peak value of electric force acting on a particle of charge 5 µC travelling with a velocity of 5 × 105 m/s along the Y-axis.
Answer» Expression for EM wave travelling along X-axis, \(\overrightarrow{B}\) = \(\hat{k}\) [4 × 10^-4 sin (ωt – kx)] Here, B₀ = 4 × 10^-4 Given: q = 5 µC = 5 × 10^-6 C v = 5 × 10⁵ m/s along Y-axis ∴ E₀ = cB₀ = 3 × 10⁸ × 4 × 10^-4 = 12 × 10⁴N/C Maximum electric force = qE₀ = 5 × 10^-6 × 12 × 10⁴ = 0.6 N

The magnetic field of an EM wave travelling along X-axis is vector B = k [4 × 10-4 sin (ωt – kx)]. Here B is in tesla, t is in second and x is in m. Calculate the peak value of electric force acting on a particle of charge 5 µC travelling with a velocity of 5 × 105 m/s along the Y-axis.

Answer»

Expression for EM wave travelling along X-axis,

\(\overrightarrow{B}\) = \(\hat{k}\) [4 × 10^-4 sin (ωt – kx)]

Here, B₀ = 4 × 10^-4

Given: q = 5 µC = 5 × 10^-6 C

v = 5 × 10⁵ m/s along Y-axis

∴ E₀ = cB₀ = 3 × 10⁸ × 4 × 10^-4

= 12 × 10⁴N/C

Maximum electric force = qE₀

= 5 × 10^-6 × 12 × 10⁴

= 0.6 N