Problem
What is the angle of the \( 2^{\text {nd }} \) order bright fringe produced by two slits that are \( 8.25 \times 10^{-5} \mathrm{~m} \) apart if the wavelength of the incident light is \( 4.50 \times 10^{-7} \mathrm{~m} \) ? \( 91.7^{\circ} \) \( 1.60^{\circ} \) \( 0.625^{\circ} \) \( 0.0109^{\circ} \)
Solution
Step 1 ：Step 1: Use the formula for bright fringes: \( \sin{\theta} = \frac{m \lambda}{d} \)
Step 2 ：Step 2: Substitute given values: \( \sin{\theta} = \frac{2 (4.50 \times 10^{-7}\mathrm{~m})}{8.25 \times 10^{-5}\mathrm{~m}} \)
Step 3 ：Step 3: Solve for \(\theta\): \( \theta = \arcsin{(0.0109)} \approx 0.625^{\circ} \)
