Mirror Equation Calculator
1/f = 1/d_o + 1/d_i. Same form as lens but with mirror sign conventions.
Result
di
30.0000 cm
Magnification -1.0000.
- f15.0000 cm
- d_o30.0000 cm
- d_i30.0000 cm
- M-1.0000
- Mirror typeConcave (converging)
- Image typeReal (in front of mirror)
Step-by-step
- Mirror equation: 1/f = 1/d_o + 1/d_i (same form as lens).
- Sign conventions: concave f positive; convex f negative.
- M = -d_i / d_o = -1.0000.
How to use this calculator
- Pick what to solve.
- Enter known values.
- Mind sign conventions for concave/convex.
About this calculator
Mirror equation: 1/f = 1/d_o + 1/d_i. Sign convention: concave (converging) f positive; convex (diverging) f negative. Real images form on the reflective side (d_i positive); virtual images appear behind the mirror (d_i negative). Concave mirrors: bathroom shaving, dental, telescope primaries. Convex mirrors: passenger side car (objects appear smaller but wider field of view).
Frequently asked
Concave: curves inward (like a spoon's bowl side). Convex: curves outward.
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