An LCD (liquid crystal display) projector works by illuminating a small LCD display-not unlike a small computer screen-with a very bright light and using a lens to form an image of the display on the viewing screen. A small LCD projector has a 5.00-cm-tall LCD display, and the lens needs to create a 1.60-m-tall image. The screen is 4.50 m from the LCD display

An inquiring student makes a refracting telescope by placing an objective lens and an eyepiece at opposite ends of a 46.5 cm long tube. If the eyepiece has a focal length of 1.70 cm, calculate the required focal length in cm of the objective lens and the angular magnification of the telescope. HINT (a) the required focal length in cm of the objective lens  cm (b) the angular magnification of the telescope

A slide projector needs to create a 96-cm-high image of a 2.0-cm-tall slide. The screen is 310 cm from the slide. part a) What focal length does the lens need? Assume that it is a thin lens. part b) How far should you place the lens from the slide?

Create a ray diagram for eyeglasses that contain a diverging lens. Assume you are looking at a 2 cm tall object that is 4 cm from the lens. The focal length is 3 cm. What type of vision are they used to correct? Give both names. How do they do this? Explain.

Problem 8: The objective lens of the refracting telescope at the Lick Observatory in California has a focal length of 57 ft. a. What is the refractive power of this lens? b. What focal length (mm) eyepiece would give a magnification of 1000X for this telescope?

A lens of focal length 42 mm is used as a magnifier. The object being viewed is 6.8 mm long, and is positioned at the focal point of the lens. The lens is moved closer to the object, so that the image is now 15 cm from the lens. The distance the lens has been moved, in cm, is closest to:

An object located 32 cm in front of a lens forms an image on a screen 8 cm behind the lens. a) Find the focal length of the lens. What type of lens is it? b) What is the magnification of the object?

(numbers 8-9) An object is placed 12 cm from a diverging lens with a focal length of -6 cm. 8. How far is the image from the lens? 4 cm 4.5 cm 6 cm 8 cm 12 cm 9. The image is: real and smaller real and larger virtual and smaller virtual and larger none of the above answers are correct

To fit a contact lens to a patient's eye, a keratometer can be used to measure the curvature of the cornea-the front surface of the eye. This instrument places an illuminated object of known size at a known distance p from the cornea, which then reflects some light from the object, forming an image of it. The magnification M of the image is measured by using a small viewing telescope that allows a comparison of the image formed by the cornea with a second calibrated image projected into the field of view by a prism arrangement. Determine the radius of curvature of the cornea whenp = 28.0 cm and M = 0.0140.