Question

An Object is placed 20cm from the concave lens. focal length of the lens is 30 cm. then find the image distance​

Answer 1

Answer:

Explanation:1/20 +1/q= 1/10 q=20 cm The image is formed behind the lens at 2f or the center ... It is real, inverted, and the same size as the object. ... The distance of object from the lens is 30 cm.

Answer 2

Answer:

•The image distance is 12cm and the image is formed in front of the mirror.

•The lens formula is given by  

1/f  = (1/v) - (1/u)

•Here f is the focal length of the lens, f= -30cm

•The object distance, u= -20cm

•hence image distance, v = -60/5 = -12 cm

•Since the image distance is a negative value, there the image formed is in front of the mirror.