Reflection of Light Worksheet with Ray Diagram and Angle Calculations

Let's solve the worksheet step by step.

---

Q1: Label the parts of ray diagram

We are given a standard reflection diagram with:

- An incident ray (coming toward the surface)
- A reflected ray (going away from the surface)
- A normal line (perpendicular to the surface at the point of incidence)
- Angles labeled as i (angle of incidence) and r (angle of reflection)

#### Labels to fill in:

From left to right, top to bottom:

1. Top center box (above the normal):
→ Normal (a line perpendicular to the reflecting surface)

2. Left side, above the incident ray:
→ Incident Ray (the incoming light ray)

3. Right side, above the reflected ray:
→ Reflected Ray (the outgoing light ray)

4. Bottom left, near the incident ray:
→ Angle of Incidence (i)

5. Bottom right, near the reflected ray:
→ Angle of Reflection (r)

6. Below the surface, inside the green block:
→ Reflecting Surface

7. The small green angle between the incident ray and the normal:
→ This is already labeled as i, so no need to label it again.

8. The small green angle between the reflected ray and the normal:
→ Already labeled as r

So the completed labels should be:

- Top center: Normal
- Left: Incident Ray
- Right: Reflected Ray
- Bottom left: Angle of Incidence (i)
- Bottom right: Angle of Reflection (r)
- Below the mirror: Reflecting Surface

---

Q2: Find the missing angles

We have a diagram with two mirrors forming a right angle (90°), and a ray incident on one mirror, then reflecting off both.

Given:
- Angle between incident ray and mirror AB = 65°
- The second reflection occurs at point C, where the angle with the horizontal mirror is 25°

Let’s analyze step by step.

---

#### Step 1: Find angle a

- The incident ray makes a 65° angle with mirror AB.
- The angle of incidence is measured from the normal, not the mirror.
- Since the normal is perpendicular to the mirror, the angle between the incident ray and the normal is:
$$
\text{Angle a} = 90^\circ - 65^\circ = 25^\circ
$$

✔ So, angle a = 25°

---

#### Step 2: Find angle b

- By the law of reflection, angle of incidence = angle of reflection.
- So, the reflected ray from mirror AB will also make 25° with the normal.
- Therefore, angle b = 25°

✔ So, angle b = 25°

---

#### Step 3: Find angle c

Now, the ray reflects from mirror AB and hits mirror BC (horizontal mirror).

We are told that at point C, the angle between the incident ray and the horizontal mirror is 25°.

But we need angle c, which is the angle of incidence at point C — i.e., the angle between the incident ray and the normal to the horizontal mirror.

Since the normal is vertical here (perpendicular to horizontal mirror), and the ray makes 25° with the mirror, then:

$$
\text{Angle c} = 90^\circ - 25^\circ = 65^\circ
$$

✔ So, angle c = 65°

---

#### Step 4: Find angle d

By the law of reflection, angle of reflection = angle of incidence.

So, the reflected ray from point C will make the same angle with the normal as the incident ray.

Thus, angle d = 65°

✔ So, angle d = 65°

---

✔ Final Answers for Q2:

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

---

🔍 Summary:

| Angle | Value | Reason |
|-------|-------|--------|
| a | 25° | 90° – 65° (complementary to incident ray and mirror) |
| b | 25° | Law of reflection (equal to angle a) |
| c | 65° | 90° – 25° (incident ray makes 25° with horizontal mirror) |
| d | 65° | Law of reflection (equal to angle c) |

---

Let me know if you'd like this explained visually or want the labeled version!