[" 13.The focal length of a concave mirror is "12" cm "],[" Where should an object of length "4cm" be placed "],[" so that a real image of "1cm" length is formed? "],[[" (1) "48cm," (2) "3cm," (3) "60cm," (4) "15cm]]

The focal length of a concave mirror is 12 cm . Where should an object of length 4 cm be placed so that a real image of 1 cm length is formed ?

The focal length of a concave mirror is 20 cm . Where should an object be placed to get an image magnified twice?

The focal length of a concave mirror is 50cm. Where an object be placed so that its image is two times and inverted

The focal length of a concave mirror is 50cm. Where an object be placed so that its image is two times and inverted

The focal length of a concave lens is 30 cm. At what distance should the object be placed from the lens so that it forms an image at 20cm from the lens?

At what distance in front of a concave mirror of focal length 10 cm, an object be placed so that its real image of size five times that of the object is obtained?

(a) A point source S is placed at a distance of 15 cm from a converging lens of focal length 10 cm on its principal axis, where should a diverging mirror of focal length 12 cm be placed so that a real image is formed on the source itself? (b) A diverging lens of focal length 20 cm and a converging mirror of focal length 10 cm are placed coaxially at separation of 5 cm. Where should an object be placed so that a real image is formed at the object itself? (c) A converging lens of focal length 12 cm and a diverging mirror of focal length 7.5 cm are placed 5.0 cm apart with the principal axis coinciding where should an object be placed so that its image falls on itself?