Question 1

In the figure, the image is viewed on a screen and is 13.5 mm tall. What is the focal length of the lens?

Accepted Answer

A)  +14.6 cm 
B)  -14.6 cm 
C)  +20.4 cm 
D)  -89.3 cm 
E)  +124 cm 
A)  +14.6 cm 
B)  -14.6 cm 
C)  +20.4 cm 
D)  -89.3 cm 
E)  +124 cm C

Question 2

The distance between the object and the eyepiece of a compound microscope is 18.0 cm. The focal length of its objective lens is 0.80 cm and the eyepiece has a focal length of 2.3 cm. The near-point distance of the person using the microscope is 25.0 cm. What is the total overall magnification of the microscope?

Accepted Answer

A)  -120 x 
B)  -184 x 
C)  -200 x 
D)  -360 x 
E)  -480 x 
A)  -120 x 
B)  -184 x 
C)  -200 x 
D)  -360 x 
E)  -480 x C

Question 3

The angular magnification of a refracting telescope is 40 x. When the object and final image are both at infinity, the distance between the eyepiece and the objective is 143.5 cm. The telescope is used to view a distant radio tower. The real image of the tower, formed by the objective, is 6.0 mm in height. The focal point of the eyepiece is positioned at the real image. What is the angle subtended by the final image of the tower.

Accepted Answer

A)  0.15 rad 
B)  0.17 rad 
C)  0.19 rad 
D)  0.21 rad 
E)  0.23 rad 
A)  0.15 rad 
B)  0.17 rad 
C)  0.19 rad 
D)  0.21 rad 
E)  0.23 rad B

Question 4

A simple refracting telescope provides large magnification by employing

Accepted Answer

A)  a short focal length objective and a short focal length eyepiece. 
B)  a short focal length objective and a long focal length eyepiece. 
C)  a long focal length objective and a short focal length eyepiece. 
D)  a long focal length objective and a long focal length eyepiece. 
A)  a short focal length objective and a short focal length eyepiece. 
B)  a short focal length objective and a long focal length eyepiece. 
C)  a long focal length objective and a short focal length eyepiece. 
D)  a long focal length objective and a long focal length eyepiece.

Question 5

An object 1.25 cm tall is placed 100 cm in front of a convex lens with a focal length of magnitude 50 cm. A concave lens with a focal length of magnitude 20 cm is placed 90 cm beyond the first lens. Where is the final image located?

Accepted Answer

A)  10 cm in front of the second lens 
B)  20 cm past the second lens 
C)  17 cm past the second lens 
D)  10 cm past the second lens 
E)  20 cm in front of the second lens 
A)  10 cm in front of the second lens 
B)  20 cm past the second lens 
C)  17 cm past the second lens 
D)  10 cm past the second lens 
E)  20 cm in front of the second lens

Question 6

An object is placed 100 cm in front of a diverging lens with a focal length of magnitude 25 cm. A converging lens having a focal length of magnitude 33.33 cm is placed 30 cm past the first lens. Where is the final image formed?

Accepted Answer

A)  30 cm after the second lens 
B)  20 cm in front of the first lens 
C)  3.0 meters before the second lens 
D)  100 cm after the second lens 
E)  3.0 cm before the second lens 
A)  30 cm after the second lens 
B)  20 cm in front of the first lens 
C)  3.0 meters before the second lens 
D)  100 cm after the second lens 
E)  3.0 cm before the second lens

Question 7

The objective and the eyepiece of a microscope have focal lengths of 4.00 mm and 25.0 mm, respectively. The objective produces a real image 30 times the size of the object. The final image is viewed at infinity, and the near point of the microscope user is at 25.0 cm. What is the distance between the object and the focal point of the objective?

Accepted Answer

A)  0.13 mm 
B)  0.18 mm 
C)  0.23 mm 
D)  0.28 mm 
E)  0.33 mm 
A)  0.13 mm 
B)  0.18 mm 
C)  0.23 mm 
D)  0.28 mm 
E)  0.33 mm

Question 8

The focal lengths of the objective and the eyepiece of a microscope are 0.50 cm and 2.0 cm, respectively, and their separation adjusted for minimum eyestrain (with the final image at the viewer's far point) is 6.0 cm. The near point of the person using the microscope is 25 cm and the far point is infinity.
(a) If the microscope is focused on a small object, what is the distance between the object and the objective lens?
(b) If the microscope is focused on a small object, what is its final magnification?

Accepted Answer

(a) 0.57 c

Question 9

A nearsighted physicist cannot see things clearly beyond 90 cm from her eyes. What is the power of the contact lenses that will enable her to see very distant objects clearly?

Accepted Answer

A)  1.1 diopters 
B)  -1.1 diopters 
C)  -1.7 diopters 
D)  -2.2 diopters 
E)  2.2 diopters 
A)  1.1 diopters 
B)  -1.1 diopters 
C)  -1.7 diopters 
D)  -2.2 diopters 
E)  2.2 diopters

Question 10

What power contact lens must be used to correct the vision of a nearsighted person whose far point is 40 cm?

Accepted Answer

A)  2.5 diopters 
B)  -2.5 diopters 
C)  -3.6 diopters 
D)  -4.0 diopters 
E)  4.0 diopters 
A)  2.5 diopters 
B)  -2.5 diopters 
C)  -3.6 diopters 
D)  -4.0 diopters 
E)  4.0 diopters

Question 11

A singer is farsighted and cannot see objects clearly that are closer than 80.0 cm from his unaided eye. What is the refractive power of the contact lenses that will move his near point to a distance of 25.0 cm from his eye?

Accepted Answer

A)  2.75 diopters 
B)  -2.75 diopters 
C)  -4.72 diopters 
D)  4.72 diopters 
E)  7.00 diopters 
A)  2.75 diopters 
B)  -2.75 diopters 
C)  -4.72 diopters 
D)  4.72 diopters 
E)  7.00 diopters

Question 12

A camera lens has a focal length of 50.0 mm and an aperture setting of f/4.00. What is the aperture diameter of this lens?

Accepted Answer

A)  12.5 mm 
B)  10.1 mm 
C)  13.6 mm 
D)  14.2 mm 
E)  15.0 mm 
A)  12.5 mm 
B)  10.1 mm 
C)  13.6 mm 
D)  14.2 mm 
E)  15.0 mm

Question 13

In the figure, the radius of curvature of the curved part of the lens is 24.0 cm, and the refractive index of the lens material is 1.750. What is the focal length of the lens?

Accepted Answer

A)  +32.0 cm 
B)  -32.0 cm 
C)  -16.0 cm 
D)  +13.8 cm 
E)  -13.8 cm 
A)  +32.0 cm 
B)  -32.0 cm 
C)  -16.0 cm 
D)  +13.8 cm 
E)  -13.8 cm

Question 14

Which statements are true about a VIRTUAL image? (There may be more than one correct choice.)

Accepted Answer

A)  Its location can be calculated, but it cannot be viewed directly by your eye without using auxiliary lenses. 
B)  It cannot be photographed. 
C)  It cannot be viewed on a screen. 
D)  A plane mirror always forms a virtual image. 
E)  A concave lens always forms a virtual image. 
A)  Its location can be calculated, but it cannot be viewed directly by your eye without using auxiliary lenses. 
B)  It cannot be photographed. 
C)  It cannot be viewed on a screen. 
D)  A plane mirror always forms a virtual image. 
E)  A concave lens always forms a virtual image.

Question 15

A goldfish bowl is spherical, 8.0 cm in radius. A goldfish is swimming 3.0 cm from the wall of the bowl. Where does the fish appear to be to an observer outside? The index of refraction of water is 1.33. Neglect the effect of the glass wall of the bowl.

Accepted Answer

A)  3.3 cm inside the bowl 
B)  3.9 cm inside the bowl 
C)  2.5 cm inside the bowl 
D)  3.0 cm inside the bowl 
E)  1.7 cm inside the bowl 
A)  3.3 cm inside the bowl 
B)  3.9 cm inside the bowl 
C)  2.5 cm inside the bowl 
D)  3.0 cm inside the bowl 
E)  1.7 cm inside the bowl

Question 16

A 4.0-cm tall object is placed 60 cm away from a converging lens of focal length 30 cm. What are the nature and location of the image? The image is

Accepted Answer

A)  real, 2.5 cm tall, and 30 cm from the lens on the same side as the object. 
B)  virtual, 2.5 cm tall, and 30 cm from the lens on the side opposite the object. 
C)  virtual, 2.0 cm tall, and 15 cm from the lens on the side opposite the object. 
D)  virtual, 4.0 cm tall, and 60 cm from the lens on the same side as the object. 
E)  real, 4.0 cm tall, and 60 cm from the lens on the side opposite the object. 
A)  real, 2.5 cm tall, and 30 cm from the lens on the same side as the object. 
B)  virtual, 2.5 cm tall, and 30 cm from the lens on the side opposite the object. 
C)  virtual, 2.0 cm tall, and 15 cm from the lens on the side opposite the object. 
D)  virtual, 4.0 cm tall, and 60 cm from the lens on the same side as the object. 
E)  real, 4.0 cm tall, and 60 cm from the lens on the side opposite the object.

Question 17

A person having a near point of 25 cm and a far point at infinity uses a converging lens of focal length 5.0 cm as a magnifying glass. What is the magnification if the person's eye is relaxed (with the image at his far point)?

Accepted Answer

The answer of A person having a near point of...

Question 18

An object is placed 100 cm in front of a lens of focal length 20 cm. A second lens is placed 35 cm beyond the first, this second lens having a focal length of 8.0 cm. If the height of the object is 6.0 cm, what is the height of the final image?

Accepted Answer

A)  1.5 cm 
B)  12 cm 
C)  9.0 cm 
D)  3.0 cm 
E)  6.0 cm 
A)  1.5 cm 
B)  12 cm 
C)  9.0 cm 
D)  3.0 cm 
E)  6.0 cm

Question 19

The objective and the eyepiece of a refracting astronomical telescope have focal lengths of 320 cm and 4.0 cm, respectively. The telescope is used to view Neptune and the final image is set at infinity. The diameter of Neptune is 4.96 × 107 m and the distance from the earth at the time of observation is 4.4 × 1012 m. What is the angle (in mrad) subtended by the final telescopic image of Neptune?

Accepted Answer

A)  0.90 mrad 
B)  1.1 mrad 
C)  1.3 mrad 
D)  1.5 mrad 
E)  1.7 mrad 
A)  0.90 mrad 
B)  1.1 mrad 
C)  1.3 mrad 
D)  1.5 mrad 
E)  1.7 mrad

Question 20

A thin converging lens is found to form an image of a distant building 24 cm from the lens. If an insect is now placed 16 cm from this lens, how far FROM THE INSECT will its image be formed?

Accepted Answer

A)  64 cm 
B)  72 cm 
C)  32 cm 
D)  96 cm 
E)  48 cm 
A)  64 cm 
B)  72 cm 
C)  32 cm 
D)  96 cm 
E)  48 cm

Exam 33: Geometric Optics

In the figure, the image is viewed on a screen and is 13.5 mm tall. What is the focal length of the lens?

A simple refracting telescope provides large magnification by employing

An object 1.25 cm tall is placed 100 cm in front of a convex lens with a focal length of magnitude 50 cm. A concave lens with a focal length of magnitude 20 cm is placed 90 cm beyond the first lens. Where is the final image located?

An object is placed 100 cm in front of a diverging lens with a focal length of magnitude 25 cm. A converging lens having a focal length of magnitude 33.33 cm is placed 30 cm past the first lens. Where is the final image formed?

A nearsighted physicist cannot see things clearly beyond 90 cm from her eyes. What is the power of the contact lenses that will enable her to see very distant objects clearly?

What power contact lens must be used to correct the vision of a nearsighted person whose far point is 40 cm?

A singer is farsighted and cannot see objects clearly that are closer than 80.0 cm from his unaided eye. What is the refractive power of the contact lenses that will move his near point to a distance of 25.0 cm from his eye?

A camera lens has a focal length of 50.0 mm and an aperture setting of f/4.00. What is the aperture diameter of this lens?

In the figure, the radius of curvature of the curved part of the lens is 24.0 cm, and the refractive index of the lens material is 1.750. What is the focal length of the lens?

Which statements are true about a VIRTUAL image? (There may be more than one correct choice.)

A goldfish bowl is spherical, 8.0 cm in radius. A goldfish is swimming 3.0 cm from the wall of the bowl. Where does the fish appear to be to an observer outside? The index of refraction of water is 1.33. Neglect the effect of the glass wall of the bowl.

A 4.0-cm tall object is placed 60 cm away from a converging lens of focal length 30 cm. What are the nature and location of the image? The image is

A person having a near point of 25 cm and a far point at infinity uses a converging lens of focal length 5.0 cm as a magnifying glass. What is the magnification if the person's eye is relaxed (with the image at his far point)?

An object is placed 100 cm in front of a lens of focal length 20 cm. A second lens is placed 35 cm beyond the first, this second lens having a focal length of 8.0 cm. If the height of the object is 6.0 cm, what is the height of the final image?

A thin converging lens is found to form an image of a distant building 24 cm from the lens. If an insect is now placed 16 cm from this lens, how far FROM THE INSECT will its image be formed?

Units, Physical Quantities, and Vectors

Motion Along a Straight Line

Motion in Two or Three Dimensions

Newtons Laws of Motion

Applying Newtons Laws

Work and Kinetic Energy

Potential Energy and Energy Conservation

Momentum, Impulse, and Collisions

Rotation of Rigid Bodies

Equilibrium and Elasticity

Fluid Mechanics

Gravitation

Periodic Motion

Mechanical Waves

Sound and Hearing

Temperature and Heat

Thermal Properties of Matter

The First Law of Thermodynamics

The Second Law of Thermodynamics

Electric Charge and Electric Field

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current, Resistance, and Electromotive Force

Direct-Current Circuits

Magnetic Field and Magnetic Forces

Sources of Magnetic Field

Electromagnetic Induction

Inductance

Alternating Current

Electromagnetic Waves

The Nature and Propagation of Light

Interference

Diffraction

Relativity

Photons: Light Waves Behaving As Particles

Particles Behaving As Waves

Quantum Mechanics

Atomic Structure

Molecules and Condensed Matter

Nuclear Physics

Particle Physics and Cosmology

Filters