Question

solve the numericals

Answer 1

1)r=40cm
f=r/2=20cm
2)similarly r=30cm
3)1:- 4m
2:- 150cm
3:- 2 m
4)in a missing angle is 35 degree
In b missing angle is 25 degree

Answer 2

Q.1
focus = radius of curvature/2
=40/2=20
therefore the focal length of the concave mirror is 20cm


Q.2
same formula as used in Q.1
radius of curvature= focus x 2
= 15 x 2 = 30cm
therefore the radius of curvature of the convex mirror is 30cm


Q.3
we know that for plane mirror
distance of object from mirror=distance of image from mirror

(i) therefore distance between Mona and her image=2 x distance of Mona from mirror=2 x 2=4m

(ii) as we know that the image formed by the plane mirror is of same size as the object
so the height of Mona's image would be 150 cm.

(iii) same as sub-part 1
2 x 1=2m

Q.4 is solved in the picture


Hope this helps you!!!