CH 24 Q 30 GoA stationary particle of charge q = 2.3 × 10-8 C is placed in a laser beam (an electromagnetic wave) whose intensity is 2.6 × 103 W/m2. 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 × 104 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.
a)
I = 0.5 E^2 / ( c uo)
2.6* 10^3 = 0.5* E^2 / (3* 10^8* 4* 3.14* 10^-7)
E = 1399.77 N/C
force experienced by charge
F = qE = 2.3* 10^-8* 1399.77 = 3.22* 10^-5 N
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b)
F = qV B = 0
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c)
F = 3.22* 10^-5 N
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d)
B = E/ c = 1399.77 / ( 3* 10^8) = 4.666* 10^-6 T
Force exerted on particle
F = q v B = 2.3* 10^-8* 3.7* 10^4* 4.666* 10^-6
F = 3.971* 10^-9 N