Answer
Image distance is -61 cm, magnification is 2.7.
Work Step by Step
Use the lens equation to find the image distance.
$$\frac{1}{f}=\frac{1}{d_o}+\frac{1}{d_i}$$
$$d_i=\frac{fd_o}{d_o-f}=\frac{(9.2cm)(8.0cm)}{8.0cm-9.2cm}=-61cm$$
b. Assume that the eye is relaxed, since the image is relatively far away compared to the near point. The angular magnification is found from equation 25-2a.
$$M=\frac{\theta ‘}{\theta}=\frac{N}{f}=\frac{25cm}{9.2cm}=2.7\times$$
Note: it is not appropriate to use $M=N/d_o$, as on page 723, because the image is not at the eye’s near point.