Answer:
(A). The order of the bright fringe is 6.
(B). The width of the bright fringe is 3.33 μm.
Explanation:
Given that,
Fringe width d = 0.5 mm
Wavelength = 589 nm
Distance of screen and slit D = 1.5 m
Distance of bright fringe y = 1 cm
(A) We need to calculate the order of the bright fringe
Using formula of wavelength


Put the value into the formula


(B). We need to calculate the width of the bright fringe
Using formula of width of fringe

Put the value in to the formula



Hence, (A). The order of the bright fringe is 6.
(B). The width of the bright fringe is 3.33 μm.
Answer:
0.0018 W/m²
Explanation:
Power and intensity are related as:

P= 20.0 W (given)
r = 30.0 m (given)

Intensity in decibels:

Answer: I am not sure if you wanted me to answer this or not.
Explanation:
I don't know about 1 but I know you should check 2 & 3 definitely