If a cat casts a 5 mm image on your retina when it is 10 ft away from you,that same cat will cast an image that is ________ mm when it is 20 ft away from you.

Question

Quizplus · Accepted Answer

The size of the image cast on the retina is inversely proportional to the distance between the object and the eye. So, if the distance increases from 10 ft to 20 ft, the size of the image will decrease proportionally. This can be calculated using the formula:

Size of image at distance 2 = Size of image at distance 1 x Distance 1 / Distance 2

So, Size of image at distance 2 = 5 mm x 10 ft / 20 ft = 2.5 mm

Therefore, the correct answer is C) 2.5.

If a Cat Casts a 5 Mm Image on Your