Solve qus no 3: 3 A thin conave and thin convex lenses are in contact The - Physics - Ray Optics And Optical Instruments

Question

Solve qus no 3:

3 A thin conave and thin convex lenses are in contact The ratio of
the magnitude of power of two lenses is 2/3 and focal length of
combination is 30 cm, then the focal lengths of individual lenses
are
(a) 75 cm, 50 cm (b) -75 cm, 50 cm
(b) 75 cm, -50 cm (d) -15 cm, 10 cm

Anshu Agrawal · Accepted Answer

Dear student,

PconcavePconvex=231F=1fconcave+1fconvex130=-23f+1ff=10cm(focal length of convex lens)f for concave will be -15cm

Option d is correct

Regards

Solve qus no. 3: 3. A thin conave and thin convex lenses are in contact. The ratio of the magnitude of power of two lenses is 2/3 and focal length of combination is 30 cm, then the focal lengths of individual lenses are. (a) 75 cm, 50 cm (b) -75 cm, 50 cm (b) 75 cm, -50 cm (d) -15 cm, 10 cm

Solve qus no. 3:

3. A thin conave and thin convex lenses are in contact. The ratio of the magnitude of power of two lenses is 2/3 and focal length of combination is 30 cm, then the focal lengths of individual lenses are.
(a) 75 cm, 50 cm (b) -75 cm, 50 cm
(b) 75 cm, -50 cm (d) -15 cm, 10 cm