186k views
5 votes
Light passes through a diffraction grating with 3550 lines/cm and forms a first-order maximum at an angle of 12.07°. At what angle will the second maximum appear?

User EboMike
by
7.7k points

1 Answer

6 votes

Answer:The angle at which the first-order maximum appears can be calculated using the formula:

sin(θ) = mλ/d

where θ is the angle at which the maximum appears, m is the order of the maximum (in this case, m=1 for the first-order maximum), λ is the wavelength of the light, and d is the spacing between adjacent lines on the diffraction grating.

We can rearrange this formula to solve for d:

d = mλ/sin(θ)

For the first-order maximum:

d = (1)(λ)/(sin(12.07°))

Now, to find the angle at which the second maximum appears, we can use the same formula but with m=2:

sin(θ) = 2λ/d

Rearranging this formula to solve for θ:

θ = arcsin(2λ/d)

Substituting the values we have already calculated:

θ = arcsin(2λ/[(1)(λ)/(sin(12.07°))])

Simplifying:

θ = arcsin(2sin(12.07°))

θ ≈ 24.17°

Therefore, the second maximum will appear at an angle of approximately 24.17°.

Explanation:

calculations:

1. We are given the number of lines per centimeter on the diffraction grating, which is 3550 lines/cm.

2.We are also given that the light forms a first-order maximum at an angle of 12.07°.

3.We can use the formula sin(θ) = mλ/d to find the spacing between adjacent lines on the diffraction grating. Rearranging this formula to solve for d, we get d = mλ/sin(θ).

4.Substituting the values m=1, λ (which we assume to be the wavelength of the light), and θ=12.07°, we can solve for d. We get d = (1)(λ)/(sin(12.07°)).

5.Next, we want to find the angle at which the second maximum appears. We can use the same formula, but with m=2: sin(θ) = 2λ/d.

6.Rearranging this formula to solve for θ, we get θ = arcsin(2λ/d).

7.Substituting the values we calculated for d and assuming the same wavelength of light, we can solve for the angle θ. We get θ = arcsin(2sin(12.07°)).

8.Finally, we evaluate this expression and get the answer: the second maximum will appear at an angle of approximately 24.17°.

User Dhruv Chandhok
by
7.9k points