Question

An electromagnetic wave of wavelength 435 nm is traveling in vacuum in the —z direction. The electric field has an amplitude of 2.70 x 10^-3 V/m and is parallel to the x axis. What are the frequency and the magnetic-field amplitude of this wave? In calculating the amplitude of the magnetic field, you divide the electric-field amplitude by the speed of light, which requires you to convert some units. Which of the following is equivalent to 1 T?

a. 1 (N/A.m)
b. 1 (N/c.m)
c. 1 (N.s/C.m)
d. 1 (V.s/m^2)

Answer 1

a) 6.9*10^14 Hz

b) 9*10^-12 T

Step-by-step explanation:

Given that

The wavelength of the wave, λ = 435 nm

Amplitude of the electric field, E(max) = 2.7*10^-3 V/m

a)

The frequency of the wave can be found by using the formula

c = fλ, where c = speed of light

f = c/λ

f = 3*10^8 / 435*10^-9

f = 6.90*10^14 Hz

b)

E(max) = B(max) * c, magnetic field amplitude, B(max) =

B(max) = E(max)/c

B(max) = 2.7*10^-3 / 3*10^8

B(max) = 9*10^-12 T

c)

1T = 1 (V.s/m^2)