Question

An object is located 5.0 cm from a concave mirror. The focal length is 15.0 cm. What is the image distance? Use the equation attached.
A.3.8 Cm
B.-3.8 Cm
C.-7.5 Cm
D.7.5 Cm

Answer 1

Answer:

-7.5 cm

Explanation:

OK so in the equation they're having you use the variables are:

$d_o = 5.0 cm\\\\f = 15.0 cm\\\\d_i = ?$

So we simply plug in the variables:

$d_i = \frac{d_of}{d_o-f} \\\\d_i = \frac{5.0 * 15.0}{5.0 - 15.0}\\\\d_i = \frac{75}{-10}\\\\d_i = -7.5 cm$