Question

2) a small candle 2.5cm in size is plated at 27cm infront of concave mirror of radius of curverture 36cm at what distance from mirror should screen be placed in order to obtain a sharp image? describe the nature and size of an image. draw diagram as well​

Answer 1

Answer:

Explanation:

Size of the candle = 2.5 cm

Image size = h

object distance, u = -27cm

Radius of curvature of the concave mirror , R= -36cm

Focal length of the concave mirror = f = r/2

                                                               -36/2 = -18 cm                  

Image distance = v

so yeah, the image distance can be obtained using the mirror formula:

                  1/u+1/v=1/f

1/v= 1/f-1/u

1/v = 1/-18-1/-27

= -3+2

    54

=   -1  

    54  

v = -54

 

Therefore, the screen should be placed 54cm away by the mirror obtain a sharp image.

The magnification of the image is given as:

m = h¹/h = -v/u

h¹ = -v/u *h

       -(-54/-27) *2.5 = -5cm

The height of the candle image is 5 cm. The negative sign indicates that the image is inverted and virtual.

If the candle is moved closer to the mirror , then the screen will have to be moved away from the mirror in order to obtain image.