Question

A concave mirror has a focal length of 0.29 m. If an object produces a real image 0.40 m from the mirror, where is it located?

Answer 1

In order to calculate the object's position, we can use the formula below:

`(1)/(f)=(1)/(d_o)+(1)/(d_i)`

Where f is the focal length, do is the object distance and di is the image distance.

So, using f = 0.29 and di = 0.4, let's solve for do:

`\begin{gathered} (1)/(0.29)=(1)/(d_o)+(1)/(0.4)\\ \\ (1)/(d_o)=(1)/(0.29)-(1)/(0.4)\\ \\ (1)/(d_o)=3.448-2.5\\ \\ (1)/(d_o)=0.948\\ \\ d_o=(1)/(0.948)\\ \\ d_o=1.055\text{ m} \end{gathered}`

Therefore the object's position is 1.055 meters.