A concave mirror has a radius of curvature of 80cm. If the real image of an object is formed at 1m, how far from the mirror is the object?
Question
Question
A concave mirror has a radius of curvature of 80cm. If the real image of an object is formed at 1m, how far from the mirror is the object?
Answer:
66.7 cm
Explanation:
The focal length is half the radius of curvature, or f = 40 cm.
The image is real, so i = +100 cm.
The distance to the object is therefore:
1/o + 1/f = 1/i
1/o + 1/40 = 1/100
o = -66.7 cm
The object is 66.7 cm left of the mirror.