A convex lens of focal length 1.0m and a concave lens of focal length 0.25m are 0.75m apart. A parallel beam of light is incident on the convex lens. The beam emerging after refraction from both lenses is

Options

A. parallel to principal axis
B. covergent
C. divergent
D. None of the above

Answer

A

Explanation

(a) Power of system=`1/(f_(1))+1/(f_(2))-d/(f_(1)f_(2))`
`=1/1+(1/(-0.25))-0.75/((1)(-0.25))`
`=1-4+3=-3+3=0`
Since, power of the system is zero, therefore the incident parallel beam of light will remain parallel after emeging from the system.