Reflection of light - Free Printable

Let’s solve this step by step.

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Q1: Label the parts of ray diagram

We are looking at a standard reflection diagram. Here’s what each part means:

- The green rectangle at the bottom is the mirror (or reflecting surface).
- The vertical dashed line going up from the mirror is called the normal — it’s perpendicular to the mirror.
- The ray coming in toward the mirror is the incident ray.
- The ray bouncing off the mirror is the reflected ray.
- The angle between the incident ray and the normal is labeled i → that’s the angle of incidence.
- The angle between the reflected ray and the normal is labeled r → that’s the angle of reflection.
- The point where all rays meet on the mirror is the point of incidence.

So, labeling from top to bottom, left to right:

Top center box (above normal):
→ Normal

Left middle box (next to incoming ray):
→ Incident Ray

Right middle box (next to outgoing ray):
→ Reflected Ray

Bottom long box (on green bar):
→ Mirror or Reflecting Surface

Left small box near “i”:
→ Angle of Incidence

Right small box near “r”:
→ Angle of Reflection

*(Note: In some diagrams, they may label the angles as just “i” and “r”, but since boxes are provided for labels, we use full names.)*

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Q2: Find the missing angles

We’re given a diagram with two mirrors meeting at a corner (like an L-shape), and light rays bouncing off them.

Let’s go step by step.

#### Step 1: Look at point B (first reflection)

At point B:
- There’s a vertical mirror.
- A ray comes in at 65° to the mirror surface (not to the normal!).
- We need to find angle a and b.

Remember: Angles in reflection are measured from the normal, not the mirror surface.

The normal at B is horizontal (since mirror is vertical).

So, if the ray makes 65° with the mirror, then the angle with the normal is:

> 90° - 65° = 25°

That means:
- Angle a = angle of incidence = 25°
- By law of reflection, angle of reflection = angle of incidence → so angle b = 25°

✔ So far:
a = 25°
b = 25°

#### Step 2: Look at point C (second reflection)

At point C:
- The mirror is horizontal.
- The ray hits the mirror and reflects.
- We’re told one angle is 25° — that’s the angle between the incoming ray and the mirror surface (written in pink).

Again, we measure angles from the normal.

Normal at C is vertical (since mirror is horizontal).

So, angle between incoming ray and normal = 90° - 25° = 65°

That’s angle c → angle of incidence = 65°

Then, angle of reflection = angle of incidence → so angle d = 65°

✔ Final values:
c = 65°
d = 65°

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Wait — let me double-check!

In the diagram at point C, the 25° is written between the ray and the mirror — yes, same as at B.

So:

At B:
Ray to mirror = 65° → to normal = 25° → a=25°, b=25° ✔️

At C:
Ray to mirror = 25° → to normal = 65° → c=65°, d=65° ✔️

Also, check if the path makes sense: After reflecting at B, the ray goes down to C. Since angle b is 25° below horizontal, and mirror at C is horizontal, the angle between that ray and the mirror should be 25° — which matches the diagram! Perfect.

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Final Answer:

Q1 Labels (from top to bottom, left to right as per typical layout):

- Top center: Normal
- Left middle: Incident Ray
- Right middle: Reflected Ray
- Bottom long box: Mirror
- Left small box near i: Angle of Incidence
- Right small box near r: Angle of Reflection

Q2 Missing Angles:

Measurement of angle a = 25
Measurement of angle b = 25
Measurement of angle c = 65
Measurement of angle d = 65