Find the amplitude of electric field produced by radiation coming from a 100 W bulb at a distance of 4 m , assuming that the bulb is a point source and its efficiency is 3.14 % .

Question

Find the amplitude of electric field produced by radiation coming from a 100 W bulb at a distance of 4 m , assuming that the bulb is a point source and its efficiency is 3.14 % . (A) 2.42 Vm- 1 (B) 14× 104 Vm- 1 (C) 4.2× 104 Vm- 1 (D) 3.43 Vm- 1

Tardigrade Admin · Accepted Answer

E0=√(P/2 π R2 Ïµ0 c) =√(3 . 14 × 100/2 × 3 . 14 × 16 × 100 × 8 . 85 × 10- 12 × 3 × 108)=3.43 Vm- 1

Q. Find the amplitude of electric field produced by radiation coming from a $100 W$ bulb at a distance of $4 m$ , assuming that the bulb is a point source and its efficiency is $3.14%$ .

$2.42 V m^{- 1}$

$14 \times 1 0^{4} V m^{- 1}$

$4.2 \times 1 0^{4} V m^{- 1}$

$3.43 V m^{- 1}$

$E_{0} = \frac{P}{2 π R ^{2} ϵ _{0} c}$
$= \frac{3.14 \times 100}{2 \times 3.14 \times 16 \times 100 \times 8.85 \times 1 0 ^{- 12} \times 3 \times 1 0 ^{8}} = 3.43 V m^{- 1}$

Q. Find the amplitude of electric field produced by radiation coming from a 100W bulb at a distance of 4m , assuming that the bulb is a point source and its efficiency is 3.14% .

2.42Vm−1

14×104Vm−1

4.2×104Vm−1

3.43Vm−1