Question

A concave mirror of focal length17.5 cm forms a real image24.8 cm from the mirror. What isthe magnification?(Mind your minus signs.)(Unit = cm)

Answer 1

We can use the mirror formula:

$\frac{1}{f}=\frac{1}{v}+\frac{1}{u}$

The focal length, f, is 17.5 cm. (remember the minus sign)

The object distance, u, is 24.8 cm. (minus sign)

We can look at the magnification equation:

$M=-\frac{u}{v}$

Now, let's plug in the numbers for u and v.

$M=-\frac{(-24.8)}{(-17.5)}$

Simplify this equation to get:

$M=-1.4171$

The magnification of the image is -1.4171 cm.