The magnetic field of a beam emerging from a fitter facing a flood light is given by B0= 12 x 10-8sin (1.2 x 107z- 3.60 x 1015 t) T What is the average intensity of the beam?

This is a short answer type question as classified in NCERT Exemplar Aaverage magnetic energy density Iav= 1 2 B 2 μ 0 c From eqn we know that B=12 * 10 - 8 = 1 2 * ( 12 * 10 - 8 ) 2 * 3 * 10 8 4 π * 10 - 7 = 1.71W/m2

The magnetic field of a beam emerging from a fitter facing a flood light is given by B₀= 12 x 10^-8sin (1.2 x 10⁷z- 3.60 x 10¹⁵ t) T What is the average intensity of the beam?

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Payal Gupta | Contributor-Level 10

7 months ago

This is a short answer type question as classified in NCERT Exemplar

Aaverage magnetic energy density I_av= $\frac{1}{2} \frac{B^{2}}{μ_{0}}$ c

From eqn we know that B=12 $* 10^{- 8}$

= $\frac{1}{2} * \frac{({12 * 10^{- 8})}^{2} * 3 * 10^{8}}{4 π * 10^{- 7}}$ = 1.71W/m²

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