Q1.
Magnification produced by a rear-view mirror fitted in vehicles is:
(a) is less than one
(b) is more than one
(c) is equal to one.
Q2.
If angle of incidence when a ray strikes a mirror is 30°, then find the angle that the reflected ray will make with the normal.
Q3.
Define principal focus of a concave mirror.
Q4.
Draw a diagram of a convex mirror and mark:
(i) pole,
(ii) focus,
(iii) centre of curvature and
(iv) principal axis.
Q5.
What is the relation between radius of curvature and focal length of spherical mirror?
Q6.
A light ray parallel to the principal axis falls on a concave mirror. Draw a ray diagram to show the reflection by the concave mirror.
Q7.
Which mirror can give an erect and enlarged image of an object.
Q8.
What is the minimum number of rays required for locating the image formed by a spherical mirror? How many rays can actually emerge from an object?
Q9.
Magnification of a spherical mirror is +2. Name the type of spherical mirror.
Q10.
What is the main advantage of using a convex mirror as a rear-view mirror in vehicles?
Q11.
Write the mirror’s formula.
Q12.
Define absolute refractive index.
Q13.
State Snell’s law.
Q14.
If the speed of light in vacuum is 3 x 108 ms-1, find the speed of light in a medium of absolute refractive index 1.5.
Q15.
Speed of light in water is 2.26 × 108 m/s and speed of light in glass is 2 × 108 m/s. Which medium is optically denser?
Q16.
Write Len’s formula.
Q17.
Define power of a lens. What is its unit?
Q18.
Find the focal length of the lens of power – 2D. What type of lens is this?
Q19.
Assertion(A) :For observing traffic at back, the driver mirror is convex mirror.
Reason (R) : A convex mirror has much larger field of view than a plane mirror.
Q20.
Assertion(A) : The height of an object is always considered positive.
Reason (R) : An object is always placed above the principal axis in this upward direction.
