1.

A candle placed 25 cm from a lens forms an image on a screen placed 75 cm on the other side of the lens. The focal length and type of the lens should be

Answer»

`+ 18.75` CM and CONVEX LENS
`-18.75` cm and CONCAVE lens
`+20.25` cm and convex lens
`-20.25` cm and concave lens

Solution :`1/f=1/v-1/u`
`1/f=1/75+1/25`
`1/f=100/(75xx25)`
`f=75/4=18.75cm`


Discussion

No Comment Found

Related InterviewSolutions