To draw incident and reflected rays, you need to understand the law of reflection and use tools like a ruler and protractor for accuracy. Here's a step-by-step guide:
Steps to Draw Incident and Reflected Rays
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Draw the Mirror: Represent the mirror as a straight line. Shade one side of the line to indicate the back of the mirror.
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Draw the Normal: Draw a line perpendicular to the mirror surface at the point where the incident ray will strike. This perpendicular line is called the normal. The normal is crucial for measuring angles.
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Draw the Incident Ray: Draw a line representing the incident ray, which is the ray of light traveling towards the mirror. This line starts from the light source (or is assumed to come from a light source) and ends at the point where it intersects the mirror (the point of incidence).
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Measure the Angle of Incidence: Use a protractor to measure the angle between the incident ray and the normal. This angle is called the angle of incidence (θi). Place the center of the protractor at the point of incidence on the mirror, and align the 0° line with the normal.
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Calculate the Angle of Reflection: According to the law of reflection, the angle of reflection (θr) is equal to the angle of incidence (θi). Therefore, θr = θi.
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Draw the Reflected Ray: Use the protractor to measure the angle of reflection (θr) from the normal on the other side of the normal from the incident ray. Draw a line from the point of incidence, extending away from the mirror at this angle. This line represents the reflected ray, which is the ray of light traveling away from the mirror.
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Label: Label the incident ray, reflected ray, normal, angle of incidence (θi), and angle of reflection (θr).
Key Points:
- The incident ray, reflected ray, and normal all lie in the same plane.
- The angle of incidence is always equal to the angle of reflection (Law of Reflection).
- Accuracy in measurement is essential for an accurate ray diagram. Use a sharp pencil and precise tools.
