Camera lenses are described in terms of their

focal length. A 50 mm lens has a focal length
of 50 mm. A camera is focused on an object
81 m away using a 88 mm lens.
Locate the position of the image.
Answer in units of mm

687

To locate the position of the image formed by the camera lens, we can use the lens equation:

1/f = 1/do + 1/di

Where:
- f is the focal length of the lens,
- do is the object distance (the distance from the lens to the object), and
- di is the image distance (the distance from the lens to the image).

We are given:
- f = 88 mm (focal length of the lens)
- do = 81 m (object distance from the lens)

To solve for di, we need to convert the object distance (do) from meters to millimeters:

do = 81 m * 1000 mm/m = 81000 mm

Now we can substitute the known values into the lens equation:

1/88 = 1/81000 + 1/di

To solve for di, we can rearrange the equation as:

1/di = 1/88 - 1/81000

To simplify the equation, we can find a common denominator:

1/di = (81000 - 88) / (81000 * 88)

Calculating the value on the right side:

1/di = 80912 / 7128000

Now, to find the value of di, we can take the reciprocal of both sides of the equation:

di = 7128000 / 80912

Calculating the value of di:

di ≈ 88.165 mm

Therefore, the position of the image formed by the camera lens is approximately 88.165 mm away from the lens.