Convex mirrors are used as driving mirrors because images formed are

1. Analyze the question

The question asks for the specific characteristics of the image formed by a convex mirror when used as a driving (side) mirror. We need to identify whether the image is upright (erect) or upside down (inverted), whether it is real or virtual, and whether it is smaller (diminished) or larger (magnified) than the object.

2. Explain the concept

• Convex Mirror: This is a spherical mirror where the reflecting surface bulges towards the source of light. It is often called a "diverging mirror."
• Image Formation: For any position of a real object in front of a convex mirror, the light rays appear to diverge from a point behind the mirror.
• Characteristics: • Erect: The image is always upright. • Virtual: The image cannot be caught on a screen because it is formed by the apparent intersection of light rays behind the mirror. • Diminished: The image is always smaller than the actual object. This is the primary reason they are used as driving mirrors—they provide a wider field of view, allowing the driver to see more of the road behind them.

3. Show the solution

• Step 1: Evaluate the nature of the image. Since convex mirrors always form images behind the mirror, the image is virtual.
• Step 2: Evaluate the orientation. The image is always upright, meaning it is erect.
• Step 3: Evaluate the size. Because the rays diverge, the image formed is always smaller than the object, meaning it is diminished.
• Step 4: Compare with the options. We are looking for "Erect, Virtual, and Diminished."

4. Identify the answer

Comparing our findings with the given options:

• A. erect, virtual and diminished (Matches our findings)
• B. erect, real and diminished (Incorrect: convex mirrors do not form real images for real objects)
• C. erect, virtual and magnified (Incorrect: convex mirrors do not magnify)
• D. inverted, virtual and diminished (Incorrect: the image is not inverted)

5. Exam Tip

To remember this easily, use the mnemonic "C-V-E-D": Convex mirrors are Virtual, Erect, and Diminished. Also, remember that convex mirrors are for "wide-angle" viewing, which is why they are perfect for security mirrors in shops and side mirrors on cars!