Combination Of Lens

We combined a convex lens of focal length f_(1) and concave lens of focal lengths f_(2) and their combined focal length was F . The combination of these lenses will behave like a concave lens, if

An eye specialist prescribes spectacles having combination of convex lens of focal length 40cm in contact with a concave lens of focal length 25cm. The power of this lens combination in diopters is

An eye specialist prescribes spectacles having combination of convex lens of focal length 40 cm in contact with a concave lens of focal length 25 cm. The power of this lens combination in diopters is

Assertion : In a compound microscope, the intermediate image is real, inverted and magnified. Reason : An eye specialist prescribes spectacles having a combination of convex lens (f = + 40 cm) in contact with a concave lens (f = – 25 cm). The power of this lens combination is – 1.5D

A convex lens of focal length 40 cm a concave lens of focal length 40 and a concave lens of focal length 15 cm are placed in contact. The power of this combination of are placed in contact. The power of this combination in diopters is

A convex lens of focal length 30 cm and a concave lens of focal length 60 cm are placed in combination. If an object is placed 40 cm away from the combination, find the position of the image.

A convex lens of power +5 D is placed in contact with a concave lens of power -4 D. What is the power of combination and nature of lens combination ?

The combination of a convex lens ( f = 18 cm ) and a thin concave lens ( f = 9 cm ) is