# The magnetic field of an electromagnetic wave is given by    = 1.6 × 10 −6 cos(2 × 107z + 6 × 1015t) The associated electric field will be (a)  = 4.8 × 102 cos(2 × 107z + 6 × 1015t) (b)  = 4.8 × 102 cos(2 × 107z  − 6 × 1015t) (c)  = 4.8 × 102 cos(2 × 107z  − 6 ×1015t) (d)  = 4.8 × 102 cos(2 × 107z + 6  × 1015t)

## Question ID - 1 :- The magnetic field of an electromagnetic wave is given by    = 1.6 × 10 −6 cos(2 × 107z + 6 × 1015t) The associated electric field will be (a)  = 4.8 × 102 cos(2 × 107z + 6 × 1015t) (b)  = 4.8 × 102 cos(2 × 107z  − 6 × 1015t) (c)  = 4.8 × 102 cos(2 × 107z  − 6 ×1015t) (d)  = 4.8 × 102 cos(2 × 107z + 6  × 1015t)

3537

Amplitude of electric field, E = B0C

= 1.6 × 10 −6 ×  × 3 × 108

= 4.8 × 102  V/m

Also  ×  is along  (the direction of propagation)

⇒   = 4.8 × 102 cos(2 × 107z + 6 × 1015t)

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