NEET2014PhysicsWave OpticsActual
If prism angle =1^ , =1.54 , distance between screen and prism (D)=0.7 ~m , distance between prism and source a=0.3 ~m , =180 nm , then in Fresnal biprism find the value of (fringe width).
Options
- A10⁻⁴ ~m
- B10⁻³ ~mm
- C10⁻⁴ m
- D10⁻³ ~m
Correct answer
B. 10⁻³ ~mm
Step-by-step solution
a=0.3 =1^ , =1.54, we know that d=2 a( -1) aligned & =2 0.3(1.54-1) 1 & =2 0.3 0.54=0.324 aligned Fringe width F= D d = 0.7 180 10⁻⁹ 0.324 = 7 180 10⁻⁶ 324 =10⁻³ ~mm