Concepts Of Physics MCQ Edition [Volume 1]PhysicsDispersion and Spectra
Two thin prisms, one of crown glass ( _r = 1.515 , _v = 1.525 ) and the other of flint glass ( _r = 1.612 , _v = 1.632 ), are positioned in contact. Each has a refracting angle of 5.0^ and they are oriented in the same direction. Compute the angular dispersion generated by this combination.
Options
- A0.10^
- B0.20^
- C0.15^
- D0.05^
Correct answer
C. 0.15^
Step-by-step solution
The angular dispersion produced by a thin prism is given by = ( _v - _r)A . For the crown glass prism: ₁ = (1.525 - 1.515) 5.0^ = 0.010 5.0^ = 0.05^ For the flint glass prism: ₂ = (1.632 - 1.612) 5.0^ = 0.020 5.0^ = 0.10^ Since the prisms are oriented in the same direction, their angular dispersions add up. Total angular dispersion = ₁ + ₂ = 0.05^ + 0.10^ = 0.15^