Question

Where is the image located when an object is placed 30 cm from a convex mirror with a focal length of 10 cm? *​

Answer 1

Answer :

Distance of object = 30cm

Focal length = 10cm

Type of mirror : convex

We have to find position of image$.$

★ Focal length of convex mirror is taken positive and that of concave mirror is taken negative.

Position of image can be calculated by using mirror formula which is given by

• 1/u + 1/v = 1/f

u denotes distance of object

v denotes distance of image

f denotes focal length

By substituting the given values,

➙ 1/u + 1/v = 1/f

➙ 1/(-30) + 1/v = 1/10

➙ 1/v = 1/10 + 1/30

➙ 1/v = 4/30

➙ v = 7.5 cm

★ Position and nature of image :

• Virtual
• Erect
• Short

Answer 2

Answer:

Using the Real Is Positive convention:

u=+30 and f=-10

1/u+1/v=1/f

1/30 + 1/v = -1/10

1/v = -1/10 - 1/30 = -3/30 - 1/30 = -4/30

v = -30/4 = -7.5 cm meaning virtual and erect. And quarter the size of the object  .