Two convex lenses A and B, each of focal length 10.0 cm, are mounted on an optical bench at 50.0 cm and 70.0 cm respectively. An object is mounted at…

For the first lens: $\displaystyle \frac{1}{v_{1}}-\frac{1}{u_{1}}=\frac{1}{f_{1}}$ $\displaystyle \frac{1}{v_{1}}+\frac{1}{30}=\frac{1}{10}$ $\displaystyle v_{1}=15 \mathrm{~cm}$ For the second lens: $\displaystyle u_{2}=-20-(-15)=-5 \mathrm{~cm}$ $\displaystyle \frac{1}{v_{2}}-\left(-\frac{1}{5}\right)=\frac{1}{10}$ On solving: $\displaystyle v_{2}=-10 \mathrm{~cm}$ Image is virtual.