20.2. Concave and Convex Mirrors http://www.ck12.org
FIGURE 20.13
A convex mirror.a. Where does the image form?
Solution:
We are givenho= 10. 0 cm,do= 20. 0 cm,and f=− 12. 0 cm
Using the mirror equation we have,
1
do+
1
di=
1
f→
1
20. 0 cm+
1
di=
1
− 12. 0 cm→
1
di=−
1
20. 0 cm−
1
12. 0 cm→
1
di=
−( 12. 0 + 20. 0 )
240 cm
di=− 7. 50 cmSince the image distance is negative, it appears on the opposite side of the mirror (as inFigure20.13) and is virtual.
b. What is the magnification?
Solution:
m=−
di
do=−
− 7. 50 cm
20. 0 cm= + 0. 375
m= 0. 375The object is reduced in size and is upright.