can someone explain to me how to do this problem ?
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Answer:
The image distance is 13.3 cm ⇒ answer B
Explanation:
* Lets study the information in the problem
- The distance between the object and the convex lens is 40.0 cm
- The lens focuses light at a distance of 10.0 cm
- The equation of the image distance is [tex]d_{i}=\frac{d_{o}f}{d_{o}-f}[/tex]
where di is the image distance, do is the object distance and f is the
distance of the focuses lens
* Lets solve the problem
∵ do = 40.0 cm
∵ f = 10.0 cm
∵ [tex]d_{i}=\frac{d_{0}f}{d_{o}-f}[/tex]
- Substitute the values of do and f in the equation
∴ [tex]d_{i}=\frac{(40.0)(10.0)}{(40.0)-(10.0)}=\frac{400.0}{30.0}=\frac{40}{3}[/tex]
∴ di = 13.3333 ≅ 13.3 cm
* The image distance is 13.3 cm