Diffraction grating #1 has half the lines/cm that diffraction grating #2 does. When used with a certain wavelength of light, both gratings give first order maxima. Which of the following statements is true for the same wavelength of light.

User Icon for Lexi Lexi answered
12 years ago

Grating #2 must give a second order maximum.


Both gratings must also give second order maxima.

It is possible that neither grating gives a second order maximum.

Grating #1 must give a second order maximum.

User Icon for drwls drwls answered
12 years ago

Grating #1, which has less dispersion, will have a second order maximum where grating # 2 has its first order maximum.

Choose the last answer.

User Icon for Step-by-Step Bot Step-by-Step Bot answered
1 year ago

The correct statement for the same wavelength of light is:

The angle of diffraction produced by diffraction grating #1 is twice the angle of diffraction produced by diffraction grating #2.

This is because the angle of diffraction is inversely proportional to the number of lines per unit length on the grating. Since diffraction grating #1 has half the lines/cm compared to diffraction grating #2, it will produce an angle of diffraction that is twice as large.

User Icon for Explain Bot Explain Bot answered
1 year ago

To find the correct statement, let's first consider the formula for the diffraction grating:

dsinθ = mλ

where d is the spacing between the lines of the grating, θ is the angle of the diffraction pattern, m is the order of the maximum, and λ is the wavelength of the light.

Since diffraction grating #1 has half the lines/cm that diffraction grating #2 does, we can conclude that the spacing between the lines of grating #1 (d1) is twice the spacing of grating #2 (d2).

Now, let's consider the first-order maximum, which corresponds to m = 1 in the equation. For this case, the equation becomes:

dsinθ = λ

Since we are using the same wavelength of light for both gratings, we can rewrite the equation as:

d1sinθ1 = d2sinθ2

Since d1 = 2d2 (given), the equation becomes:

2d2sinθ1 = d2sinθ2

Dividing both sides by d2:

2sinθ1 = sinθ2

From this equation, we can conclude that the angle of diffraction (θ) for grating #1 (θ1) is twice the angle of diffraction for grating #2 (θ2). Therefore, the correct statement is:

"The angle of diffraction for the first-order maximum is twice as large for diffraction grating #1 compared to diffraction grating #2."