Chapter 10: Reflection and Refraction- Exercise- 1
Science
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Chapter 10: Reflection and Refraction
Class: X
Exercise: 1
Question 1
Define the principal focus of a concave mirror.
Answer 1
The principal focus of a concave mirror is point at which light incident towards the mirror and traveling parallel to the principal axis meet after reflection from the mirror.
Question 2
The radius of curvature of a spherical mirror is 20 cm. What is its focal length?
Answer 2
Radius of curvature of a spherical mirror, R = 20 cm
Hence, the focal length of the given spherical mirror is 10 cm.
Question 3
Name the mirror that can give an erect and enlarged image of an object.
Answer 3
Concave mirror. The image formed is virtual, erect, and enlarged when an object is placed between the pole and the principal focus of a concave mirror.
Question 4
Why do we prefer a convex mirror as a rear-view mirror in vehicles?
Answer 4
We prefer a convex mirror as a rear-view mirror in vehicles because a highly-diminished image is formed thus making the traffic look much smaller. As a result, we can see a large number of vehicles in a very small mirror.
