Question

A 15.0 cm object is 12.0 cm from a convex mirror that has a focal length of -6.0 cm. What is the height of the image produced by the mirror?

• -5.0 cm
• 7.5 cm
• -7.5 cm
• 5.0 cm

Answer 1

D. 5.0 cm

Step-by-step explanation:

got it correct on the test

Answer 2

5.0cm

Step-by-step explanation:

To get the height of the image, we will use the magnification formula as shown:

m = Hi/H = v/u

Hi is the image height

H is the object height

v is the image distance

u is the object distance

First, we need to get the image distance v

Using the mirror formula;

1/f = 1/v+ 1/u

1/-6 = 1/v + 1/12

1/v = -1/12 - 1/6

1/v = -1-2/12

1/v = -3/12

v = 12/-3cm

v = -4cm

Next is to get the image height Hi

Using the expression;

Hi/H = v/u

Hi/15 = 4/12

Hi/15 = 1/3

3Hi = 15

Hi = 15/3

Hi = 5.0cm

Hence the image height is 5.0cm