A concave mirror has a radius of curvature of 36cm. At wh...
A concave mirror has a radius of curvature of 36cm. At what distance from the mirror should an object be placed to give a real image three times the size of the object?
12cm
24cm
48cm
108cm
Correct answer is B
F = uvu+v
v = 3u
18 = 3u×u3u+u
u = 24cm
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