Physics
A car engineer tested different types of mirrors for side-view purposes.
One mirror produced accurately-sized images but with a limited field of view. Another mirror produced smaller images but provided a wider field of view.
(a) Which type of mirror should be preferred for side-view purposes? Give reason.
(b) State the quality of the image formed by the mirror answered by you above in (a).
(c) Can the same mirror be used as a doctor's head mirror? Give reason.
(d) State two other uses of the mirror used above in (a).
Answer
(a) A convex mirror should be preferred for side-view purposes because it provides a wider field of view. This allows the driver to see a larger area of the road and traffic behind the vehicle.
(b) A convex mirror forms images that are virtual, erect and diminished.
(c) No, a convex mirror cannot be used as a doctor’s head mirror because a doctor requires a bright, magnified image, which is provided by a concave mirror, not a convex mirror.
(d) Two other uses of a convex mirror are:
- Reflector in street lamps
- Road safety mirrors at blind turns
Related Questions
Assertion (A) : For an object placed symmetrically when the angle θ between the mirrors is 72°, the number of images formed is 4.
Reason (R) : If n = 360°/θ is odd, the number of images for an object placed symmetrically is equal to n.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Assertion (A) : Concave mirror is used as doctor's head mirror.
Reason (R) : If a parallel beam of light is incident on a concave mirror, the mirror focuses the beam to a point.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Assertion (A) : A student is given a spherical mirror of focal length -10 cm. He identifies it as a concave mirror.
Reason (R) : Focal length of a concave mirror is always positive.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
A student stands between two parallel plane mirrors facing each other. Later, one of the plane mirrors is replaced with a convex mirror.
(a) Why are multiple images formed between two plane mirrors?
(b) When one plane mirror is replaced by a convex mirror, predict how the number and nature of images will change.
(c) If the two plane mirrors are kept perpendicular to each other, what will be the number of images formed?
(d) How many mirrors are used in a kaleidoscope and at what angle are they inclined?