Two lenses of focal lengths 20 cm and – 40 cm are held in contact. The image of an object at infinity will be formed by the combination at
A. 10 cm
B. 20 cm
C. 40 cm
D. infinity
Answer:C
Two lenses of focal lengths 20 cm and – 40 cm are held in contact. The image of an object at infinity will be formed by the combination at
A. 10 cm B. 20 cm C. 40 cm D. infinity