The magnetic field of a plane electromagnetic wave is given by: `vec(B)=B_(0)hat(i)-[cos(kz- omegat)]+B_(1)hat(j)cos(kz+omegat)` where `B_(0)=3xx10^(-5)T` and `B_(1)=2xx10^(-6)T`. The rms value of the force experienced by a stationary charge `Q=10^(-4)C` at `z=0` is close to:

Options

A. `0.9 N`
B. `0.6 N`
C. `0.1 N`
D. `3 xx 10^(-2) N`

Answer

B

Explanation

electric field and mangnetic that option (a) is correct related as ` E = Bc `
` vecE_0 =(3 xx 10^(-5) ) c ( - hatj )`
` vecE_0 = ( 2 xx 10^(-6) ) c (- hati)`
maximum eletric force can be calculated as follows
` vecF _(" net") = q vecE_0`
` vecF _("net ") = 10^(-4) xx 3 xx 10^8 sqrt( 3 xx10^(-5) )^(2) + (2xx 10^(-6) )^(2))=0.9N`
`F_(rms ) = (F_0 )/( sqrt(2)) = 0.6 N` (approx )
hence option (b) is correct .