University Physics Volume 3
17th Edition
ISBN: 9781938168185
Author: William Moebs, Jeff Sanny
Publisher: OpenStax
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Textbook Question
Chapter 2, Problem 41P
Referring to the electric room heater considered in problem 5, calculate the intensity of IR
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Chapter 2 Solutions
University Physics Volume 3
Ch. 2 - What are the differences between real and virtual...Ch. 2 - Can you see a virtual image? Explain your...Ch. 2 - Can you photograph a virtual image?Ch. 2 - Can you project a virtual image onto a screen?Ch. 2 - Is it necessary to project a real image onto a...Ch. 2 - Devise an arrangement of mirrors allowing you to...Ch. 2 - If you wish to see your entire body in a flat...Ch. 2 - At what distance is an image always located: at...Ch. 2 - Under what circumstances will an image be located...Ch. 2 - What is meant by a negative magnification? What is...
Ch. 2 - Can an image be larger than the object even though...Ch. 2 - Derive the formula for the apparent depth of a...Ch. 2 - Use a ruler and a protractor to find the image by...Ch. 2 - You can argue that a that piece of glass, such as...Ch. 2 - When you focus a camera, you adjust the distance...Ch. 2 - A thin lens has two focal points, one on either...Ch. 2 - Will the focal length of a lens change when it is...Ch. 2 - If the lens of a person’s eye is removed because...Ch. 2 - When laser light is shone into a relaxed...Ch. 2 - Why is your vision so blurry when you open your...Ch. 2 - It has become common to replace the...Ch. 2 - If the cornea is to be reshaped (this can be done...Ch. 2 - Geometric optics describes the interaction of...Ch. 2 - The image produced by the microscope in Figure...Ch. 2 - If you want your microscope or telescope to...Ch. 2 - Consider a pair of flat mirrors that are...Ch. 2 - Consider a pair of flat mirrors that are...Ch. 2 - By using more than one flat mirror, construct a...Ch. 2 - The following figure shows a light bulb between...Ch. 2 - Why are diverging mirrors often used for rearview...Ch. 2 - Some telephoto cameras use a mirror rather than a...Ch. 2 - Calculate the focal length of a mirror formed by...Ch. 2 - Electric room heaters use a concave mirror to...Ch. 2 - Find the magnification of the heater element in...Ch. 2 - What is the focal length of a makeup mirror that...Ch. 2 - A shopper standing 3.00 m from a convex security...Ch. 2 - An object 1.50 cm high is held 3.00 cm from a...Ch. 2 - Ray tracing for a flat mirror shows that the image...Ch. 2 - Show that, for a flat mirror, hi=ho, given that...Ch. 2 - Use the law of reflection to prove that the focal...Ch. 2 - Referring to the electric room heater considered...Ch. 2 - Two mirrors are inclined at an angle of 60 ° and...Ch. 2 - Two parallel mirrors are facing each other and are...Ch. 2 - An object is located in air 30 cm from the vertex...Ch. 2 - An object is located in air 30 cm from the vertex...Ch. 2 - An object is located in water 15 cm from the...Ch. 2 - An object is located in water 30 cm from the...Ch. 2 - An object is located in air 5 cm from the vertex...Ch. 2 - Derive the spherical interface equation for...Ch. 2 - How far from the lens must the film in a camera...Ch. 2 - A certain slide projector has a 100 mm-focal...Ch. 2 - A doctor examines a mole with a 15.0-cm focal...Ch. 2 - A camera with a 50.0-mm focal length lens is being...Ch. 2 - A camera lens used for taking close-up photographs...Ch. 2 - Suppose your 50.0 mm-focal length camera lens is...Ch. 2 - What is the focal length of a magnifying glass...Ch. 2 - The magnification of a book held 7.50 cm from a...Ch. 2 - Suppose a 200 mm-focal length telephoto lens is...Ch. 2 - A camera with a 100 mm-focal length lens is used...Ch. 2 - Use the thin—lens equation to show that the...Ch. 2 - An object of height 3.0 cm is placed 5.0 cm in...Ch. 2 - An object of height 3.0 cm is placed at 5.0 cm in...Ch. 2 - Au object of height 3.0 cm is placed at 25 cm in...Ch. 2 - Two convex lenses of focal lengths 20 cm and 10 cm...Ch. 2 - What is the power of the eye when viewing an...Ch. 2 - Calculate the power of the eye when viewing an...Ch. 2 - The print in many books averages 3.50 mm in...Ch. 2 - Suppose a certain person’s visual acuity is such...Ch. 2 - People who do very detailed work close up, such as...Ch. 2 - What is the far point of a person whose eyes have...Ch. 2 - What is the near point of a person whose eyes have...Ch. 2 - (a) A laser reshaping the cornea of a myopic...Ch. 2 - The power for normal close vision is 54.0 D. In a...Ch. 2 - For normal distant vision, the eye has a power of...Ch. 2 - The power for normal distant vision is 50.0 D. A...Ch. 2 - A student’s eyes, while reading the blackboard,...Ch. 2 - The power of a physician’s eyes is 53.0 D while...Ch. 2 - The normal power for distant vision is 50.0 D. A...Ch. 2 - The far point of a myopic administrator is 50.0...Ch. 2 - A very myopic man has a far point of 20.0 cm. What...Ch. 2 - Repeat the previous problem for eyeglasses held...Ch. 2 - A myopic person sees that her contact lens...Ch. 2 - Repeat the previous problem for glasses that are...Ch. 2 - The contact lens prescription for a mildly...Ch. 2 - If the image formed on the retina subtends an...Ch. 2 - What is the magnification of a magnifying lens...Ch. 2 - How far should you hold a 2.1 cm-focal length...Ch. 2 - You hold a 5.0 cm-focal length magnifying glass as...Ch. 2 - You view a mountain with a magnifying glass of...Ch. 2 - You view an object by holding a 2.5 cm-focal...Ch. 2 - A magnifying glass forms an image 10 cm on the...Ch. 2 - An object viewed with the naked eye subtends a 2°...Ch. 2 - For a normal, relaxed eye, a magnifying glass...Ch. 2 - What range of magnification is possible with a 7.0...Ch. 2 - A magnifying glass produces an angular...Ch. 2 - A microscope with an overall magnification of 800...Ch. 2 - (a) What magnification is produced by a 0.150...Ch. 2 - Where does an object need to be placed relative to...Ch. 2 - An amoeba is 0.305 cm away from the 0.300 cm-...Ch. 2 - Unreasonable Results Your friends show you an...Ch. 2 - What is the angular magnification of a telescope...Ch. 2 - Find the distance between the objective and...Ch. 2 - A large reflecting telescope has an objective...Ch. 2 - A small telescope has a concave mirror with a...Ch. 2 - A 7.5 binocular produces an angular magnification...Ch. 2 - Construct Your Own Problem Consider a telescope of...Ch. 2 - Trace rays to find which way the given ray will...Ch. 2 - Copy and draw rays to find the final image in the...Ch. 2 - A concave mirror of radius of curvature 10 cm is...Ch. 2 - An object of height 3 cm is placed at 25 cm in...Ch. 2 - An object of height 3 cm is placed at a distance...Ch. 2 - An object of height 2 cm is placed at 50 cm in...Ch. 2 - Two concave mirrors are placed facing each other....Ch. 2 - A lamp of height S cm is placed 40 cm in front of...Ch. 2 - Parallel rays from a faraway source strike a...Ch. 2 - Parallel rays from a faraway source strike a...Ch. 2 - A light bulb is placed 10 cm from a plane mirror,...Ch. 2 - A point source of light is 50 cm in front of a...Ch. 2 - Copy and trace to find how a horizontal ray from S...Ch. 2 - Copy and trace how a horizontal ray from S comes...Ch. 2 - Copy and draw rays to figure out the final image.Ch. 2 - By ray tracing or by calculation, find the place...Ch. 2 - A diverging lens has a focal length of 20 cm. What...Ch. 2 - Two lenses of focal lengths of f1and f2are glued...Ch. 2 - What will be the angular magnification of a convex...Ch. 2 - What will be the formula for the angular...Ch. 2 - Use a ruler and a protractor to draw rays to find...Ch. 2 - Where should a 3 cm tall object be placed in front...Ch. 2 - A 3 cm tall object is placed 5 cm in front of a...Ch. 2 - You are looking for a mirror so that you can see a...Ch. 2 - Derive the following equation for a convex mirror:...Ch. 2 - (a) Draw rays to form the image of a vertical...Ch. 2 - Use another ray-tracing diagram for the same...Ch. 2 - You photograph a 2.0-m-tall person with a camera...Ch. 2 - Find the focal length of a thin plano-convex lens....Ch. 2 - Find the focal length of a meniscus lens with...Ch. 2 - A nearsighted man cannot see objects clearly...Ch. 2 - A mother sees that her child’s contact lens...Ch. 2 - Repeat the previous problem for glasses that are...Ch. 2 - The contact-lens prescription for a nearsighted...Ch. 2 - Unreasonable Results A boy has a near point of 50...Ch. 2 - Find the angular magnification of an image by a...Ch. 2 - Let objective and eyepiece of a compound...Ch. 2 - Draw rays to scale to locate the image at the...Ch. 2 - The objective and the eyepiece of a microscope...Ch. 2 - A far-sighted person has a near point of 100 cm....Ch. 2 - A near-sighted person has afar point of 80 cm. (a)...Ch. 2 - In a reflecting telescope the objective is a...Ch. 2 - Two stars that are 109km apart are viewed by a...Ch. 2 - What is the angular size of the Moon if viewed...Ch. 2 - An unknown planet at a distance of 1012 m from...
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