You are observing a 20 cm-tall object in a pinhole camera (with a screen at the end like those you used in lab/recitation this week). The screen is 25 cm from the pinhole. The image on the screen is 5 cm tall. (Note: try to do this problem without a calculator since the calculations involved are the type you would be expected to be able to do on an exam without using a calculator.) 1. If you moved the screen farther from the the pinhole, the image on the screen would:

a. Stay in focus but decrease in size
b. stay in focus but increase in size
c. lose focus

2. If you were looking at two objects, one 50 cm from the pinhole and one 75 cm from the pinhole, which object would be in 'focus' on the screen?

a. Can't determine from the information
b. the 50 cm object would be in focus
c. both objects would be in focus
d. the 75cm object would be in focus