The figure is a scaled diagram of an object and a converging lens surrounded by air.Only one focal point,F,of the lens is shown.

-The index of refraction of this lens is 1.51 for red light and 1.53 for blue light.Blue light is focused at the point F.Which one of the following statements is true concerning the focal point for red light?
A)It is also at F.
B)It is very close to D.
C)It is very close to the lens.
D)It is to the left of and close to F.
E)It is to the right of and close to F.

Question

The figure is a scaled diagram of an object and a converging lens surrounded by air.Only one focal point,F,of the lens is shown.
 
-The index of refraction of this lens is 1.51 for red light and 1.53 for blue light.Blue light is focused at the point F.Which one of the following statements is true concerning the focal point for red light?
A)It is also at F. 
B)It is very close to D. 
C)It is very close to the lens. 
D)It is to the left of and close to F. 
E)It is to the right of and close to F.

Quizplus · Accepted Answer

The index of refraction is higher for blue light than for red light, meaning blue light bends more when passing through the lens. Therefore, the focal point for red light, which bends less, will be further from the lens than that for blue light, making it to the right of and close to F.

The Figure Is a Scaled Diagram of an Object and a Converging