Question

7. A concave mirror is a part of sphere of radius 40 cm. What is the focal length of the mir
8. Radius of curvature of a mirror is 20 cm. What type of mirror is it?
9. Magnification of a mirror is +2/3. What type of mirror is it?​

Answer 1

Answer:

7. Radius of mirror=40cm

focal length=R/2

=40/2

=20cm by converting it into metre

=20/100

=0.2m

8.Radius of curvature of mirror is 20cm which is positive hence the mirror is convex

9.+2/3 magnification produced by mirror (+)sign shows that image formed is virtual and erect so the mirror is convex because only convex lens can give virtual and erect image but object when kept between focus and pole of a concave mirror it also gives a virtual abd erect image so we can say that it is either convex or concave