An object is kept at a far off distance in front of a convex lens of focal length 15 cm. State the position of the image.

An object is placed at a distance of 20 cm in front of a concave mirror of focal length 10 cm. Determine the position of the image. What is the ratio of the size of the image to the size of the object ?

An object is placed at a distance of 60 cm in front of a concave mirror of focal length 30 cm. Where will the image be formed? If the object apporoaches d cm towards the mirror, then how far will the image be shifted?

A 2.0cm tall object is placed 15cm in front of a concave mirror of focal length 10cm. What is the size and nature of the image?

A concave mirror of focal length 36 cm and a convex mirror of focal length 20 cm are placed face to face on the same axis at a distance of separation 80 cm. An object is placed at a distance 20 cm in front of the convex mirror. Determine the position of the images (i) first by the reflection in convex mirror and then in the concave mirror and (ii) first by the reflection in concave mirror and then in the convex mirror.

An object is kept in front of a concave mirror of focal length 15 cm. The image formed is three times the size of the object. Calculate two possible distances of the object from the mirror.

An object is placed at the distance of 30 cm from a concave mirror of focal length 15 cm. The image will be-

If the object and image distance is 30 cm of a convex lense then its focal length is

An object is placed 20 cm from a convex lens of focal length 10 cm. The image must be-