A set of narrow vertical slits is located a distance D from a screen. The slits

Question

A set of narrow vertical slits is located a distance D from a screen. The slits are equally spaced and have the same width. The intensity pattern in the figure is observed when light from a laser passes through the slits, illuminating them uniformly. The screen is perpendicular to the direction of the light. Data: Distance to the screen = 2.17 m, Wavelength of light = 620 nm, Distance between tick marks on the intensity figure = 1.20 cm.

1. What is the spacing between the slits?

2. Calculate the width of the slits.

3. If the slit separation is increased by a factor of 3, what would be the distance between the principal peaks on the screen?

Explanation / Answer

lambda = 620 nm ; y = 1.2 cm ; L = 2.17 m

1)We know that

dy/L = lambda

d = lambda L/y

d = 620 x 10^-9 x 2.17/(1.2 x 10^-2) = 1.12 x 10^-4 m

Hence, d = 1.14 x 10^-4 m = 11.4 micro-m

b)width will be:

a = lambda L/5 y

a = 620 x 10^-9 x 2.17/(5 x 1.2 x 10^-2) = 2.24 x 10^-5 m

Hence, a = 2.24 x 10^-5 m = 22.4 micro-m

c)y' = lambda L/d' = lambda L/3d

y' = y/3 = 1.2/3 =0.4 cm

Hence, y' = 0.4 cm

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.