Calculating Object Height Using a Pinhole Camera

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To calculate the height of an object using a pinhole camera, one can apply the principles of similar triangles. Given that the object is 100m away and the image produced is 5cm high on a screen 10cm from the pinhole, the height of the object can be determined through proportional relationships. Participants suggest drawing a diagram to visualize the setup, which aids in understanding the geometry involved. A link to a resource for finding a suitable diagram is provided for further assistance. Utilizing these methods will lead to the correct calculation of the object's height.
MoniMini
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I don't have any idea how to go about this...
Please help!:frown:

A pinhole camera produces an image of an object kept at a distance of 100m from the pin hole. If the screen is 10 cm from the pin hole and the image is 5 cm high, what is the height of the object

Any help will be appreciated :smile:

Thank You!
 
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Draw the diagram and similar triangles will give you the answer.
 
grzz said:
Draw the diagram and similar triangles will give you the answer.

There is no diagram attached to the question :rolleyes:
 
Try the web for a diagram.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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