Question

Determine the image distance and image height for a 5.00 cm tall object placed 45.0 cm from a double convex lens with a focal length of 15.0 cm.

Answer 1

Given,

object distance = Given that, an object placed 45.0 cm from a convex lens having a focal length of 15.0 cm

and the height of the image is 5.0 cm

we know,

`\begin{gathered} (1)/(f)=(1)/(v)-(1)/(u)\frac{}{} \\ \\ (1)/(15)=(1)/(v)-(1)/(-45) \\ \\ (1)/(v)=(1)/(15)-(1)/(45) \\ \\ (1)/(v)=(2)/(45) \\ \\ \therefore\text{ v=22.5cm} \end{gathered}`

we know,

`\begin{gathered} (h_i)/(h_o)=(v)/(u) \\ \\ \frac{\begin{equation*}h_i\end{equation*}}{5}=(22.5)/(-45) \\ \\ h_i=-2.5cm \end{gathered}`

result,

image distance = 22.5cm towards right side of convex lens .

image height=2.5cm, {Enlarged and inverted}