A point object is 36 cm from a concave mirror. Its transverse magnification magnitude is 1.5. Find |f| in centimetres for the real-image case.
Physics · Geometrical optics · spherical mirror
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Question

A point object is 36 cm from a concave mirror. Its transverse magnification magnitude is 1.5. Find |f| in centimetres for the real-image case.

G1 Physics · Accepted Answer

For real image M=1.5, u=f(1+1/M)=f(1+2/3)=5f/3. Thus f=3u/5=21.6 cm.