Question

An object 3 cm high  is placed  40 cm in front of a concave spherical mirror with radius of curvature of 60 centimeters and an image of the object is observed.

part a Make a drawing of the system

part b Explain how you would calculate the focal length  and the position of the image.

part c Calculate the height of the image.

part d Indicate if the image is real or virtual and if it is upright or inverted.

Answer 1

given
object height, h = 3 cm
object distance, u = 40 cm
radius of curvature, R = 60 cm

a)

b) focal length, f = R/2 = 60/2 = 30 cm
let v is the image distance.

use, 1/u + 1/v = 1/f

1/v = 1/f - 1/u

1/v = 1/30 - 1/40

v = 120 cm <<<<<<<----------------Answer

part c) magnification, m = -v/u

= -120/40

= -3

image height, h' = m*object hight

= -3*3

= -9 cm <<<<<<<----------------Answer

part d) The image is real and inverted.