Question 1

The corrective lenses of a person suffering from which vision ailment could be used to start a fire?

Accepted Answer

A)  Myopia 
B)  no eyeglass lenses can be used to make a fire. 
C)  astigmatism 
D)  hyperopia 
E)  cataracts 
A)  Myopia 
B)  no eyeglass lenses can be used to make a fire. 
C)  astigmatism 
D)  hyperopia 
E)  cataracts D

Question 2

A concave mirror has a radius of 2.0 m.What is the refractive power of a lens of the same focal length as the mirror?

Accepted Answer

A)  0.50 D 
B)  1.0 D 
C)  2.0 D 
D)  0.75 D 
E)  -0.50 D 
A)  0.50 D 
B)  1.0 D 
C)  2.0 D 
D)  0.75 D 
E)  -0.50 D B

Question 3

Two converging lenses,the first with focal length 25 cm and the second with focal length 20 cm,are separated by 30 cm.A 4.0 cm tall object is placed 50 cm in front of the first lens.What is the height of the final image?

Accepted Answer

A)  4.0 cm 
B)  2.0 cm 
C)  8.0 cm 
D)  9.3 cm 
E)  1.0 cm 
A)  4.0 cm 
B)  2.0 cm 
C)  8.0 cm 
D)  9.3 cm 
E)  1.0 cm B

Question 4

A small object has an angular diameter of 0.50$^{\circ}$.When viewed through a magnifier,it has an angular diameter of 8.0$^{\circ}$.What is the angular magnification in this case?

Accepted Answer

A)  4.0 
B)  8.0 
C)  16 
D)  32 
E)  8.5 
A)  4.0 
B)  8.0 
C)  16 
D)  32 
E)  8.5

Question 5

Which statement best explains why we are able to see details of a distant object more clearly?

Accepted Answer

A)  the image formed by the telescope is larger than the object 
B)  the image formed by the telescope subtends a larger angle at the eye than the object does 
C)  the intermediate image formed by the objective lens is greatly magnified 
D)  both the objective and eyepiece form real images 
A)  the image formed by the telescope is larger than the object 
B)  the image formed by the telescope subtends a larger angle at the eye than the object does 
C)  the intermediate image formed by the objective lens is greatly magnified 
D)  both the objective and eyepiece form real images

Question 6

To get the same exposure on the film,when the aperture diameter of a camera lens is doubled,what change should be made in the shutter speed?

Accepted Answer

A)  it should be doubled 
B)  it should be halved 
C)  it should be quadrupled 
D)  it should be quartered 
E)  it should be reduced by a factor of 1.414 
A)  it should be doubled 
B)  it should be halved 
C)  it should be quadrupled 
D)  it should be quartered 
E)  it should be reduced by a factor of 1.414

Question 7

A compound microscope has three possible objective lenses and two eyepiece lenses For maximum angular magnification,the objective (f0)and eyepiece (fe)should be chosen such that

Accepted Answer

A)  f0 and fe are both the largest available. 
B)  f0 and fe are both the smallest available. 
C)  f0 is the largest available: fe is the smallest available. 
D)  f0 is the is the smallest available: fe is the largest available. 
A)  f0 and fe are both the largest available. 
B)  f0 and fe are both the smallest available. 
C)  f0 is the largest available: fe is the smallest available. 
D)  f0 is the is the smallest available: fe is the largest available.

Question 8

An astronomical telescope has a barrel length of 33 cm and an angular magnification of 10.What are the focal lengths of the objective and the eyepiece in that order?

Accepted Answer

A)  0.3 m, 3 m 
B)  30 cm, 3 cm 
C)  20 cm,13 cm 
D)  3 cm, 30 cm 
A)  0.3 m, 3 m 
B)  30 cm, 3 cm 
C)  20 cm,13 cm 
D)  3 cm, 30 cm

Question 9

Of the following distances,which is the closest an object can be to a lens of focal length f and still give a real image?

Accepted Answer

A)  3f 
B)  2f 
C)  1.2f 
D)  0.8f 
E)  0.49f 
A)  3f 
B)  2f 
C)  1.2f 
D)  0.8f 
E)  0.49f

Question 10

There are two lenses in a microscope because

Accepted Answer

A)  the objective is a converging lens and the eyepiece is a diverging lens. 
B)  the objective is a diverging lens and the eyepiece is a diverging lens. 
C)  the objective is a diverging lens and the eyepiece is a converging lens. 
D)  the objective is a converging lens and the eyepiece is a converging lens. 
A)  the objective is a converging lens and the eyepiece is a diverging lens. 
B)  the objective is a diverging lens and the eyepiece is a diverging lens. 
C)  the objective is a diverging lens and the eyepiece is a converging lens. 
D)  the objective is a converging lens and the eyepiece is a converging lens.

Question 11

You use a camera with a lens whose focal length is 50.00 mm,and are taking a picture of a 2.500 m tall statue that is located 7.200 m from the lens.If the image height on the film is 18.20 mm,what is the distance from the lens to the film?

Accepted Answer

A)  5.035 cm 
B)  need more information 
C)  6.32 mm 
D)  5.242 cm 
A)  5.035 cm 
B)  need more information 
C)  6.32 mm 
D)  5.242 cm

Question 12

Decreasing the focal length of the eyepiece in a compound microscope by 50% changes the magnification to _______ times the previous magnification.

Accepted Answer

A)  0.50 
B)  1.5 
C)  1.7 
D)  2.0 
E)  4.0 
A)  0.50 
B)  1.5 
C)  1.7 
D)  2.0 
E)  4.0

Question 13

Two converging lenses,the first with focal length 10.0 cm and the second with focal length 20.0 cm,are separated by 40.0 cm.An object,3.00 cm in height,is placed 30.0 cm in front of the first lens.Which of the following characteristics does the final image have?

Accepted Answer

A)  real and upright 
B)  real and inverted 
C)  virtual and upright 
D)  virtual and inverted 
E)  none of these choices are correct 
A)  real and upright 
B)  real and inverted 
C)  virtual and upright 
D)  virtual and inverted 
E)  none of these choices are correct

Question 14

A fixed focus camera has a focal length of 35.0 mm.How far must the lens be moved in order to change focus from an object that is 20.0 m away to one that is 3.0 m away?

Accepted Answer

A)  0.34 mm 
B)  0.41 mm 
C)  0.35 mm 
D)  0.47 mm 
A)  0.34 mm 
B)  0.41 mm 
C)  0.35 mm 
D)  0.47 mm

Question 15

The image area on 35 mm film is 24 mm $\times$ 36 mm.What focal length lens of the following will allow an image of the moon,0.50$^{\circ}$ in diameter,to just fit on the film?

Accepted Answer

A)  2.8 m 
B)  1.4 m 
C)  0.85 m 
D)  12 mm 
E)  55 mm 
A)  2.8 m 
B)  1.4 m 
C)  0.85 m 
D)  12 mm 
E)  55 mm

Question 16

An astronomical telescope is made with lenses of focal length 80.0 cm and 2.00 cm.Two stars in the sky are separated by 0.080$^{\circ}$.What angle of separation do they have when viewed in the telescope?

Accepted Answer

A)  40$^{\circ}$ 
B)  6.4$^{\circ}$ 
C)  3.2$^{\circ}$ 
D)  1.6$^{\circ}$ 
E)  0.080$^{\circ}$ 
A)  40$^{\circ}$ 
B)  6.4$^{\circ}$ 
C)  3.2$^{\circ}$ 
D)  1.6$^{\circ}$ 
E)  0.080$^{\circ}$

Question 17

A lens has a refractive power of -1.50.What is its focal length?

Accepted Answer

A)  150 cm 
B)  -150 cm 
C)  67.0 cm 
D)  -67.0 cm 
E)  8.50 cm 
A)  150 cm 
B)  -150 cm 
C)  67.0 cm 
D)  -67.0 cm 
E)  8.50 cm

Question 18

How is chromatic aberration corrected in large astronomical reflecting telescopes?

Accepted Answer

A)  a combination of lenses designed to cancel the aberrations 
B)  use a parabolic mirror instead of a spherical mirror 
C)  a properly constructed telescope has no aberration 
D)  change the resolution of the telescope 
A)  a combination of lenses designed to cancel the aberrations 
B)  use a parabolic mirror instead of a spherical mirror 
C)  a properly constructed telescope has no aberration 
D)  change the resolution of the telescope

Question 19

A simple magnifier of refractive power 15.0 D is used to observe a beetle on a student's desk.If the image of the beetle is twice as large as the beetle itself,where is the image formed relative to the lens?

Accepted Answer

A)  4.5 cm 
B)  8.3 cm 
C)  5.0 cm 
D)  3.6 cm 
E)  5.6 cm 
A)  4.5 cm 
B)  8.3 cm 
C)  5.0 cm 
D)  3.6 cm 
E)  5.6 cm

Question 20

The lens of a slide projector has a focal length of 10.0 cm.It is used to project the image of a 35 mm slide (24 mm $\times$ 36 mm)on a square screen located 6.0 m away.Of the following screen widths,which is the smallest that would allow the image to fit?

Accepted Answer

A)  5.1 m 
B)  4.4 m 
C)  2.2 m 
D)  1.1 m 
E)  0.88 m 
A)  5.1 m 
B)  4.4 m 
C)  2.2 m 
D)  1.1 m 
E)  0.88 m

Exam 24: Optical Instruments

The corrective lenses of a person suffering from which vision ailment could be used to start a fire?

A concave mirror has a radius of 2.0 m.What is the refractive power of a lens of the same focal length as the mirror?

Two converging lenses,the first with focal length 25 cm and the second with focal length 20 cm,are separated by 30 cm.A 4.0 cm tall object is placed 50 cm in front of the first lens.What is the height of the final image?

A small object has an angular diameter of 0.50 ∘^{\circ}∘ .When viewed through a magnifier,it has an angular diameter of 8.0 ∘^{\circ}∘ .What is the angular magnification in this case?

Which statement best explains why we are able to see details of a distant object more clearly?

To get the same exposure on the film,when the aperture diameter of a camera lens is doubled,what change should be made in the shutter speed?

A compound microscope has three possible objective lenses and two eyepiece lenses For maximum angular magnification,the objective (f0)and eyepiece (fe)should be chosen such that

An astronomical telescope has a barrel length of 33 cm and an angular magnification of 10.What are the focal lengths of the objective and the eyepiece in that order?

Of the following distances,which is the closest an object can be to a lens of focal length f and still give a real image?

There are two lenses in a microscope because

You use a camera with a lens whose focal length is 50.00 mm,and are taking a picture of a 2.500 m tall statue that is located 7.200 m from the lens.If the image height on the film is 18.20 mm,what is the distance from the lens to the film?

Decreasing the focal length of the eyepiece in a compound microscope by 50% changes the magnification to _______ times the previous magnification.

Two converging lenses,the first with focal length 10.0 cm and the second with focal length 20.0 cm,are separated by 40.0 cm.An object,3.00 cm in height,is placed 30.0 cm in front of the first lens.Which of the following characteristics does the final image have?

A fixed focus camera has a focal length of 35.0 mm.How far must the lens be moved in order to change focus from an object that is 20.0 m away to one that is 3.0 m away?

The image area on 35 mm film is 24 mm ×\times× 36 mm.What focal length lens of the following will allow an image of the moon,0.50 ∘^{\circ}∘ in diameter,to just fit on the film?

An astronomical telescope is made with lenses of focal length 80.0 cm and 2.00 cm.Two stars in the sky are separated by 0.080 ∘^{\circ}∘ .What angle of separation do they have when viewed in the telescope?

A lens has a refractive power of -1.50.What is its focal length?

How is chromatic aberration corrected in large astronomical reflecting telescopes?

A simple magnifier of refractive power 15.0 D is used to observe a beetle on a student's desk.If the image of the beetle is twice as large as the beetle itself,where is the image formed relative to the lens?

The lens of a slide projector has a focal length of 10.0 cm.It is used to project the image of a 35 mm slide (24 mm ×\times× 36 mm)on a square screen located 6.0 m away.Of the following screen widths,which is the smallest that would allow the image to fit?

Introduction

Force

Acceleration and Newtons Second Law of Motion

Motion With Constant Acceleration

Circular Motion

Conservation of Energy

Linear Momentum

Torque and Angular Momentum

Fluids

Elasticity and Oscillations

Waves

Sound

Temperature and the Ideal Gas

Heat

Thermodynamics

Electric Forces and Fields

Electric Potential

Electric Current and Circuits

Magnetic Forces and Fields

Electromagnetic Induction

Alternating Current

Electromagnetic Waves

Reflection and Refraction of Light

Interference and Diffraction

Relativity

Early Quantum Physics and the Photon

Quantum Physics

Nuclear Physics

Particle Physics

Filters

A small object has an angular diameter of 0.50 $^{\circ}$ .When viewed through a magnifier,it has an angular diameter of 8.0 $^{\circ}$ .What is the angular magnification in this case?

A compound microscope has three possible objective lenses and two eyepiece lenses For maximum angular magnification,the objective (f₀)and eyepiece (fe)should be chosen such that

The image area on 35 mm film is 24 mm $\times$ 36 mm.What focal length lens of the following will allow an image of the moon,0.50 $^{\circ}$ in diameter,to just fit on the film?

An astronomical telescope is made with lenses of focal length 80.0 cm and 2.00 cm.Two stars in the sky are separated by 0.080 $^{\circ}$ .What angle of separation do they have when viewed in the telescope?

The lens of a slide projector has a focal length of 10.0 cm.It is used to project the image of a 35 mm slide (24 mm $\times$ 36 mm)on a square screen located 6.0 m away.Of the following screen widths,which is the smallest that would allow the image to fit?