Problem
A \( 5.00 \mathrm{~cm} \) tall object is placed \( 4.00 \mathrm{~cm} \) from a convex mirror with a focal length of \( 7.50 \mathrm{~cm} \). What is the distance of the image from the mirror? \( -0.383 \mathrm{~cm} \) \( -0.117 \mathrm{~cm} \) \( -8.57 \mathrm{~cm} \) \( -2.61 \mathrm{~cm} \)
Solution
Step 1 ：\( \frac{1}{d_i} = \frac{1}{f} - \frac{1}{d_o} \)
Step 2 ：\( \frac{1}{d_i} = \frac{1}{-7.50} - \frac{1}{4.00} \)
Step 3 ：\( d_i = -2.6087 \mathrm{~cm} \)
