91Ó°ÊÓ

An object is \(125 \mathrm{~cm}\) in front of a concave mirror with focal length \(75.0 \mathrm{~cm}\). (a) Where is the image? (b) Is it real or virtual? (c) What's the magnification?

A small lightbulb \(2.0 \mathrm{~m}\) from a concave mirror gives a real image \(6.0 \mathrm{~cm}\) from the mirror. (a) Find the mirror's focal length. (b) Where will the image be if the bulb is moved to \(4.0 \mathrm{~m}\) from the mirror?

A small lightbulb is \(35 \mathrm{~cm}\) in front of a concave mirror with focal length \(21 \mathrm{~cm}\). What are the location, magnification, and orientation (upright or inverted) of the bulb's image?

You have a handheld mirror that gives a virtual image of your face, enlarged by a factor of \(1.5,\) when you hold the mirror \(30 \mathrm{~cm}\) away. What's the mirror's focal length?

A concave mirror has focal length \(50 \mathrm{~cm}\). You want this mirror to form a real image 1.2 times larger than an object. (a) Where should you place the object? (b) Draw a ray diagram to locate the image. (c) Where should you place the same object so there's a virtual image 1.2 times larger than the object?

A dentist's mirror produces an upright image of a tooth, magnified three times. (a) Is the mirror concave or convex? (b) If the dentist holds the mirror \(2.0 \mathrm{~cm}\) from the tooth to achieve this magnification, what's the mirror's focal length?

A car's outside rear-view mirror is convex, with focal length \(-1.0 \mathrm{~m}\). In the mirror you see a truck that's actually \(3.5 \mathrm{~m}\) tall and \(10.0 \mathrm{~m}\) behind you. What are its apparent height and location?

A spherical mirror is silvered on both sides, so it's concave on one side and convex on the other. When an object is \(60 \mathrm{~cm}\) from one side, a real image forms \(30 \mathrm{~cm}\) from that side. (a) Find the curvature radius. (b) Describe the image if the same object is held \(60 \mathrm{~cm}\) from the other side of the mirror.

The speed of light in a new type of plastic is measured at \(2.11 \times 10^{8} \mathrm{~m} / \mathrm{s}\). What is its refractive index?

A diver shines a flashlight upward toward the water surface. Describe what happens when the flashlight beam strikes the water's surface with these angles, measured from the normal: (a) \(20^{\circ} ;\) (b) \(40^{\circ}\); (c) \(60^{\circ}\).