Which type of mirror is usually used as a rear-view mirror in motor cars ?

Explanation

To determine which type of mirror is used as a rear-view mirror in motor cars, we can follow these steps:

### Step 1: Understand the Types of Mirrors
There are three main types of mirrors:
1. **Plane Mirrors**: These produce images that are the same size as the object and are virtual and erect.
2. **Concave Mirrors**: These can produce real and inverted images or virtual and erect images depending on the position of the object.
3. **Convex Mirrors**: These always produce virtual, erect, and diminished images regardless of the object's position.

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