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
To ensure that the deviation of the mean ray is zero, a flint glass...
To ensure that the deviation of the mean ray is zero, a flint glass prism and a crown glass prism are to be combined. For the mean ray, the refractive indices of the flint and crown glasses are and , respectively. Determine the refracting angle of the crown prism if the flint prism has a refracting angle of 6.0^{}^{{}^{\circ}}.
Options
- A6.4^{}^{{}^{\circ}}
- B5.0^{}^{{}^{\circ}}
- C5.6^{}^{{}^{\circ}}
- D7.2^{}^{{}^{\circ}}
Correct answer
D. 7.2^{}^{{}^{\circ}}
Step-by-step solution
For a combination of prisms to produce zero deviation for the mean ray, the net deviation must be zero. The deviation produced by a thin prism is given by .
The condition for zero deviation is:
Given:
A_f = 6.0^{}^{{}^{\circ}}
Substituting the given values into the condition:
(1.518 - 1)A_c = (1.620 - 1) \times 6.0^{}^{{}^{\circ}}
0.518 A_c = 0.620 \times 6.0^{}^{{}^{\circ}}
0.518 A_c = 3.72^{}^{{}^{\circ}}
A_c = \dfrac{3.72^{}^{{}^{\circ}}}{0.518}
A_c \approx 7.18^{}^{{}^{\circ}}
Rounding to one decimal place, we get 7.2^{}^{{}^{\circ}}.
The condition for zero deviation is:
Given:
A_f = 6.0^{}^{{}^{\circ}}
Substituting the given values into the condition:
(1.518 - 1)A_c = (1.620 - 1) \times 6.0^{}^{{}^{\circ}}
0.518 A_c = 0.620 \times 6.0^{}^{{}^{\circ}}
0.518 A_c = 3.72^{}^{{}^{\circ}}
A_c = \dfrac{3.72^{}^{{}^{\circ}}}{0.518}
A_c \approx 7.18^{}^{{}^{\circ}}
Rounding to one decimal place, we get 7.2^{}^{{}^{\circ}}.