A concave mirror forms real images with magnifications −4 and −6 at two positions. If image positions differ by 30 cm, find the object displacement in centimetres.
Physics · Geometrical optics · spherical mirror
JEE Mains NEET

Question

A concave mirror forms real images with magnifications −4 and −6 at two positions. If image positions differ by 30 cm, find the object displacement in centimetres.

G1 Physics · Accepted Answer

From Δv=2f=30, f=15. u₁=f(1+1/4)=18.75 and u₂=f(1+1/6)=17.5. Displacement=1.25 cm.