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Physics · Light · Plane mirror
Reflection from a plane mirror
A ray of light strikes a plane mirror. Locating pins trace the reflected ray. Measure the angle of incidence and the angle of reflection from the normal — they should be equal. Repeat for five different angles to confirm the law of reflection.
angle of incidence (from normal)
30.0° → reflected: 30.0°
Results table
| i target (°) | i measured (°) | r measured (°) |
|---|---|---|
| 20 | — | — |
| 30 | — | — |
| 40 | — | — |
| 50 | — | — |
| 60 | — | — |
Exam-style questions
1. What is the relationship between angle of incidence (i) and angle of reflection (r)?
2. What is the 'normal' in a reflection diagram?
3. Image formed by a plane mirror is described as:
4. Why must locating pins be observed from a low angle, lined up exactly?