Question

A student has three concave mirrors A, B and C of focal lengths 20 cm, 15 cm and 10 cm respectively. For each concave mirror he performs the experiment of image formation for three values of object distance of 35 cm, 10 cm and 20 cm. Giving reason answer the following: (a)For the three object distances, identify the mirror which will form an image equal in size to that of object. (b)Out of the three mirrors, identify the mirror which would be preferred to be used for shaving purpose. (c)For the mirror B, draw ray diagram for image formation for any two given values of object distance.​

Answer 1

Answer:

Object distances for these mirrors are 30cm, 10cm and 20cms respectively. 1) Mirror c will produce image of same size as object because object is placed on c. 2) Mirror B can used as shaving mirror because when object is kept inbetween P and F we get virtual , erect and magnified image.