Suppose you have a pinhole camera which is 5 cm long between the hole and the film. You photograph a 1 cm long bug that is 10 cm in front of the pinhole. How long will the image of the bug be on the film?
Draw a diagram, similar triangles, ratio is 1/2
If you google pinhole camera you will find diagrams in the images.
To determine the length of the image of the bug on the film of the pinhole camera, we can use the basic principles of geometric optics.
Let's assume that the image distance is represented by "b" and the object distance is represented by "a". The pinhole camera forms an image by projecting the rays of light from the object through the small hole (pinhole) onto the film.
We can use the similar triangles concept to find the relationship between the object distance, image distance, and their respective sizes. In this case, we have:
Object length / Object distance = Image length / Image distance
Given that the object length (the bug) is 1 cm, the object distance (the distance of the bug from the pinhole) is 10 cm, and the camera length (distance from the pinhole to the film) is 5 cm, we can set up the equation as follows:
1 cm / 10 cm = Image length / (10 cm + 5 cm)
Simplifying the equation yields:
1/10 = Image length / 15
Now, we can solve for the image length:
Image length = (1/10) * 15 = 1.5 cm
Therefore, the image of the bug on the film will be 1.5 cm long.