# Home Work 7

Topics: Optics, Lens, Focal length Pages: 6 (826 words) Published: March 7, 2015
Home Work 7

3/3/15, 9:30 AM

Home Work 7
Due: 11:59pm on Monday, March 9, 2015
You will receive no credit for items you complete after the assignment is due. Grading Policy

Problem 23.08
A solar cooker, really a concave mirror pointed at the Sun, focuses the Sun's rays 19.3

cm in front of the mirror.

Part A

r=

Problem 23.09

Part A
How far from a concave mirror (radius 23.4

cm ) must an object be placed if its image is to be at infinity?

d=

Problem 23.12
A dentist wants a small mirror that, when 2.50

cm from a tooth, will produce a 5.0 × upright image.

Part A
What kind of mirror must be used?
convex
concave

https://session.masteringphysics.com/myct/assignmentPrintView?assignmentID=3348581

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Home Work 7

3/3/15, 9:30 AM

Part B

r=

Problem 23.13
You are standing 3.0
actual height.

m from a convex security mirror in a store. You estimate the height of your image to be half of your

Part A

r=

Problem 23.21
A shaving or makeup mirror is designed to magnify your face by a factor of 1.40 when your face is placed 22.0 it.

cm in front of

Part A
What type of mirror is it?
convex
concave

Part B
Describe the type of image that it makes of your face.
https://session.masteringphysics.com/myct/assignmentPrintView?assignmentID=3348581

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Home Work 7

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upright, real and reduced
inverted, real and reduced
inverted, virtual and magnified
upright, virtual and magnified

Part C

r=

Problem 23.30
A light beam coming from an underwater spotlight exits the water (n = 1.33) at an angle of 53.5∘ .

Part A
At what angle of incidence did it hit the air-water interface from below the surface? Express your answer using three significant figures.

θ=

Problem 23.36
The critical angle for a certain liquid-air surface is 47.5∘ .

Part A
What is the index of refraction of the liquid?

https://session.masteringphysics.com/myct/assignmentPrintView?assignmentID=3348581

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Home Work 7

3/3/15, 9:30 AM

n=

Problem 23.44
A certain lens focuses light from an object 1.65

m away as an image 48.3 cm on the other side of the lens.

Part A
What type of lens is it?
converging
diverging

Part B
What is its focal length? Follow the sign conventions.

f=

Part C
Is the image real or virtual?
real
virtual

Problem 23.51

Part A
How far from a 41.0-mm-focal-length lens must an object be placed if its image is to be magnified 3.50 × and be real? https://session.masteringphysics.com/myct/assignmentPrintView?assignmentID=3348581

Page 4 of 6

Home Work 7

3/3/15, 9:30 AM

d o1 =

Part B
How far from a 41.0-mm-focal-length lens must an object be placed if its image is to be magnified 3.50 × and be virtual?

d...