A stationary particle of charge q 22 Times 10B C is placed

A stationary particle of charge q = 2.2 Times 10^-B C is placed in a laser beam (an electromagnetic wave) whose intensity is 2.8 Times 10^3 W/m^2. Determine the maximum magnitude of the (a) electric and (b) magnetic forces exerted on the charge. If the charge is moving at a speed of 3.7 Times 10^4 m/s perpendicular to the magnetic field of the electromagnetic wave, find the maximum magnitudes of the (c) electric and (d) magnetic forces exerted on the particle.

Solution

Given

q = 2.2*10^-8 C

I = 2.8*10^3 W/m^2

v = 3.7*10^4 m/sec

A. I = E^2/(2*c*uo)

E = sqrt(2*c*uo*I) = sqrt(2*3*10^8*4*3.14*10^-7*2.8*10^3)

E = 1452.61 N/C

F = qE = 2.2*10^-8*1452.61

F = 3.19*10^-5 N

2. F = 0 because the charge is stationary

3. F = qE = 3.19*10^-5 N

4. F = qVB

B = E/c

F = qvE/c = 2.2*10^-8*3.7*10^4*1452.61/(3*10^8) = 3.94*10^-9 N

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