Two narrow slits are .3mm apart. When a laser shines on them, bright spots form

Question

Two narrow slits are .3mm apart. When a laser shines on them, bright spots form on the screen that is on meter away. These bright spots are 2 mm apart. The wavelength of the laser light is 6.0214 * 10^-7 m.

The 4th bright spot cannot be seen due to the first order destructive interference of the single slit diffraction. What is the size of the slits?

Explanation / Answer

Given that      b = 0.3 x 10-3 m      D = 1 m      y2 - y1 = 2 x 10-3 m      = 6.0214 x 10-7 m For destructive interference                 y2 - y1 = D / (a + b) ==>         a + b = D / y2 - y1                   a + 0.3 x 10-3 = 6.0214 x 10-7   x 1 /2 x 10-3 = 0.30107 x 10-3    Therefore the size of the slit is                   a = 0.30107 x 10-3 - 0.3 x 10-3                      = 0.00107 x 10-3 m

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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