IF SOMEONE IS ONLINE PLEASE ANS THESE Qs FASSTT!! GOT BOARDSSS!!!!!
1. Two thin lenses of focal lengths 10 cm and -5 cm are kept in contact. What is the focal length and power of the combination?
2. An image 2 cm high is placed at a distance of 16 cm from a concave mirror which produces a real image 3 cm high. Find the position of the image and the focal length of the mirror.
3. An object placed at a distance of 10 cm from a concave mirror produced an infinitely large image at the infinity. The focal length of the mirror is?
4. A concave mirror produces a real inverted image of the same size as that of the object. If the object is placed at a distance of 16 cm from the mirror, the focal length of the mirror is?