A converging lens has a focal length of 20.0 cm. Locate the image for object distances of (a) 40.0 cm, (b)20.0 cm, and (c) 10.0 cm. For each case, state whether the image is real or virtual and upright or inverted.Find the magnification in each case.

You hold a magnifying glass 4.0 cm above  1.98 mm-long bug and the image is 5.44 mm long. What is the focal length of the lens? Please give your answer in cm.

Be sure to include the correct sign (±) for each of the numerical answers on this question. You are having trouble reading your cheat sheet during the physics exam because you wrote so small. You foresaw the problem, so you brought a small lens with you to the exam. You hold the lens 5 cm away from the page. The image you see is upright and 2.5 times the size of the writing on the page. (a) Where is image formed? (Find the image distance) di = cm (b)Is the image real or virtual? (c) What is the focal length of the lens? f = cm (d) Are you using a converging lens or a diverging lens?

A convex lens of focal length 22.2 cm has an object located on its principal axis, 50.8 cm from the vertical axis of the lens. What is the height of the object (in cm) if the height of the image produced is 1.2 cm? Your answer must have at least 4 decimal places and be within 1% of the correct value. Note: You are required to insert a negative or positive number ONLY in the space provided.