Concepts Of Physics MCQ Edition [Volume 1]
- Exam
- Concepts Of Physics MCQ Edition [Volume 1]
- Subject
- Physics
- Chapter
- Dispersion and Spectra
Concepts Of Physics MCQ Edition [Volume 1] · Physics · Dispersion and Spectra
As the colour of light varies from red to violet, the refractive...
As the colour of light varies from red to violet, the refractive index of a material changes by , while that of another material changes by . Two thin prisms, one constructed from (A = 5.3^{}^{{}^{\circ}}) and the other from (A' = 3.7^{}^{{}^{\circ}}), are joined with their refracting angles similarly directed. Determine the angular dispersion produced by this combination.
Options
- A0.0888^{}^{{}^{\circ}}
- B0.163^{}^{{}^{\circ}}
- C0.0146^{}^{{}^{\circ}}
- D0.179^{}^{{}^{\circ}}
Correct answer
B. 0.163^{}^{{}^{\circ}}
Step-by-step solution
The angular dispersion produced by a thin prism is given by .
For the first prism, the angular dispersion is:
\theta_1 = \Delta \mu_1 A_1 = 0.014 \times 5.3^{}^{{}^{\circ}} = 0.0742^{}^{{}^{\circ}}
For the second prism, the angular dispersion is:
\theta_2 = \Delta \mu_2 A_2 = 0.024 \times 3.7^{}^{{}^{\circ}} = 0.0888^{}^{{}^{\circ}}
Since the two prisms are joined with their refracting angles similarly directed, their individual angular dispersions will add up.
Total angular dispersion
\theta = 0.0742^{}^{{}^{\circ}} + 0.0888^{}^{{}^{\circ}} = 0.163^{}^{{}^{\circ}}
For the first prism, the angular dispersion is:
\theta_1 = \Delta \mu_1 A_1 = 0.014 \times 5.3^{}^{{}^{\circ}} = 0.0742^{}^{{}^{\circ}}
For the second prism, the angular dispersion is:
\theta_2 = \Delta \mu_2 A_2 = 0.024 \times 3.7^{}^{{}^{\circ}} = 0.0888^{}^{{}^{\circ}}
Since the two prisms are joined with their refracting angles similarly directed, their individual angular dispersions will add up.
Total angular dispersion
\theta = 0.0742^{}^{{}^{\circ}} + 0.0888^{}^{{}^{\circ}} = 0.163^{}^{{}^{\circ}}