Alight bulb emits light uniformly in all directions. the average emitted power is 150.0 w. at a distance of 5 m from the bulb, determine (a) the average intensity of the light, (b) the rms value of the electric field, and (c) the peak value of the electric field.

a) 0.477 W/m²

b) 13.407 N/C

c) 18.96 N/C

Explanation:

P = Power = 150 W

r = Distance = 5 m

ε₀ = Permittivity of space = 8.854×10⁻¹² F/m

a) Average intensity

∴ Average intensity is 0.477 W/m²

b) Rms value

∴ Rms value of the electric field is 13.407 N/C

c) Peak value

∴ Peak value of the electric field is 18.96 N/C

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees.