A hollow lens is made of thin glass and in the shape of a double concave lens. It can be filled with air, water of refractive index 1.33 or CS ₂ of refractive index 1.6 . It will act as a diverging lens if it is

Step-by-step solution

_ air =1 _ water =1.33 _ cs ₂ =1.6 array l 1 f = ( n ₂ n ₁ -1 ) [- 1 R ₁ - 1 R ₂ ] 1 f =- ( n ₂ n ₁ -1 ) [ 1 R ₁ + 1 R ₂ ] array for diverging lens f must be - ve . for this n ₂ n ₁ >1 n ₂> n ₁ Lens should be filled with liquid which has more refractive index in comparison to liquid in which lens is immersed. Ans (D) is the correct option as _ ₂ > _ water