Question 1

A convex lens has focal length f.If an object is located extremely far from the lens (at infinity),the image formed is located what distance from the lens?

Accepted Answer

A) infinity 
B) 2f 
C) between f and 2f 
D) f 
E) between the lens and f 
A) infinity 
B) 2f 
C) between f and 2f 
D) f 
E) between the lens and f

Question 2

The left-hand end of a glass rod is ground to a spherical surface.The glass has index of refraction 1.50.A small object 4.00 mm tall is placed on the axis of the rod,37.0 cm to the left of the vertex of the spherical surface.The image is formed in the rod,50.0 cm to the right of the vertex.
(a)What is the magnitude of the radius of curvature of the spherical surface at the end of the rod?
(b)What is the height of the image?

Accepted Answer

(a)8.8 cm

Question 3

A concave spherical mirror with a radius of 20 cm creates a real image 30 cm from the mirror.How far is the object from the mirror?

Accepted Answer

A) 50 cm 
B) 20 cm 
C) 15 cm 
D) 7.5 cm 
E) 5.0 cm 
A) 50 cm 
B) 20 cm 
C) 15 cm 
D) 7.5 cm 
E) 5.0 cm

Question 4

An oil layer that is 5.0 cm thick is spread smoothly and evenly over the surface of water on a windless day.What is the angle of refraction in the water for a ray of light that has an angle of incidence of 45° as it enters the oil from the air above? (The index of refraction for the oil is 1.15,and for water it is 1.33.)

Accepted Answer

A) 27° 
B) 32° 
C) 36° 
D) 39° 
E) 52° 
A) 27° 
B) 32° 
C) 36° 
D) 39° 
E) 52°

Question 5

A tank holds a 1.44-m thick layer of oil that floats on a 0.96-m thick layer of brine.Both liquids are clear and do not intermix.Point O is at the bottom of the tank,on a vertical axis.The indices of refraction of the oil and the brine are 1.40 and 1.52,respectively.A ray originating at O reaches the brine-oil interface at the critical angle.What is the distance of this point from the axis?

Accepted Answer

A) 1.5 m 
B) 1.7 m 
C) 1.9 m 
D) 2.1 m 
E) 2.3 m 
A) 1.5 m 
B) 1.7 m 
C) 1.9 m 
D) 2.1 m 
E) 2.3 m

Question 6

Suppose you place your face in front of a concave mirror.Which one of the following statements is correct?

Accepted Answer

A) If you position yourself between the center of curvature and the focal point of the mirror,you will not be able to see a sharp image of your face. 
B) No matter where you place yourself,a real image will be formed. 
C) Your image will always be inverted. 
D) Your image will be diminished in size. 
E) None of these statements is true. 
A) If you position yourself between the center of curvature and the focal point of the mirror,you will not be able to see a sharp image of your face. 
B) No matter where you place yourself,a real image will be formed. 
C) Your image will always be inverted. 
D) Your image will be diminished in size. 
E) None of these statements is true.

Question 7

It is desired to project the image of an object four times its actual size using a lens of focal length 20 cm.How far from the lens should the object be placed?

Accepted Answer

A) 100 cm 
B) 80 cm 
C) 4.0 cm 
D) 25 cm 
E) 5.0 cm 
A) 100 cm 
B) 80 cm 
C) 4.0 cm 
D) 25 cm 
E) 5.0 cm

Question 8

A ray of light passes from glass into a liquid,as shown in the figure.What is the speed of the light in the liquid? (c = 3.00 × 108 m/s)

Accepted Answer

Question 9

In the figure,the thin lens forms a real image of the object 94.0 cm from the object.What is the focal length of the lens?

Accepted Answer

A) 22.0 cm 
B) 25.5 cm 
C) 27.5 cm 
D) 55.8 cm 
E) 86.0 cm 
A) 22.0 cm 
B) 25.5 cm 
C) 27.5 cm 
D) 55.8 cm 
E) 86.0 cm

Question 10

A convex spherical mirror with a focal length of magnitude 25 cm has a 4.0-cm tall flower placed 100 cm in front of it.What is the height of the image of the flower?

Accepted Answer

A) 0.80 cm 
B) 20 cm 
C) 4.0 cm 
D) 1.6 cm 
E) 8.0 cm 
A) 0.80 cm 
B) 20 cm 
C) 4.0 cm 
D) 1.6 cm 
E) 8.0 cm

Question 11

Light in air is initially traveling parallel to the face AC of an equilateral triangular prism,as shown in the figure.The prism is made of glass with an index of refraction of 1.52.If the light does not strike the face AC,what is the angle between the ray as it leaves the prism at face BC and the normal in air at that face?

Accepted Answer

A) 83° 
B) 19° 
C) 59° 
D) 27° 
E) 55° 
A) 83° 
B) 19° 
C) 59° 
D) 27° 
E) 55°

Question 12

A compound lens is made by joining the plane surfaces of two thin plano-convex lenses of different glasses.The radius of curvature of each convex surface is 80 cm.The indices of refraction of the two glasses are 1.50 and 1.60.What is the focal length of the compound lens?

Accepted Answer

A) 67 
B) 69 
C) 71 
D) 73 
E) 75 
A) 67 
B) 69 
C) 71 
D) 73 
E) 75

Question 13

A ray of light strikes a boundary between two transparent materials,and there is no transmitted ray,as shown in the figure.What can you conclude about the indices of refraction of these two materials?

Accepted Answer

A) n1 ≥ n2 
B) n1 > n2 
C) n1 = n2 
D) n2 ≥ n1 
E) n2 > n1 
A) n1 ≥ n2 
B) n1 > n2 
C) n1 = n2 
D) n2 ≥ n1 
E) n2 > n1

Question 14

A glass plate whose index of refraction is 1.56 is immersed in a liquid.The surface of the glass is inclined at an angle of 42.0° with the vertical.A horizontal ray in the glass is incident on the interface.When the liquid is a certain alcohol,the incident ray arrives at the interface at the critical angle.What is the index of refraction of the alcohol?

Accepted Answer

A) 1.04 
B) 1.02 
C) 1.00 
D) 0.984 
E) 1.06 
A) 1.04 
B) 1.02 
C) 1.00 
D) 0.984 
E) 1.06

Question 15

A lens is made with a focal length of -40 cm using a material with index of refraction 1.50.A second lens is made with the SAME GEOMETRY as the first lens,but using a material having refractive index of 2.00.What is the focal length of the second lens?

Accepted Answer

A) -40 cm 
B) -80 cm 
C) -53 cm 
D) -20 cm 
E) -30 cm 
A) -40 cm 
B) -80 cm 
C) -53 cm 
D) -20 cm 
E) -30 cm

Question 16

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 17

As you walk away from a vertical plane mirror,your image in the mirror

Accepted Answer

A) is always the same height. 
B) may or may not decrease in height,depending on where the observer is positioned. 
C) is always a real image,no matter how far you are from the mirror. 
D) changes from being a virtual image to a real image as you pass the focal point. 
E) decreases in height. 
A) is always the same height. 
B) may or may not decrease in height,depending on where the observer is positioned. 
C) is always a real image,no matter how far you are from the mirror. 
D) changes from being a virtual image to a real image as you pass the focal point. 
E) decreases in height.

Question 18

An optical system comprises in turn,from left to right: an observer,a lens of focal length +30 cm,an erect object 20 mm high,and a convex mirror of radius 80 cm.The object is between the lens and the mirror,20 cm from the lens and 50 cm from the mirror.The observer views the image that is formed first by reflection and then by refraction.What is the position of the final image,measured from the mirror?

Accepted Answer

A) 90 cm 
B) 102 cm 
C) 114 cm 
D) 126 cm 
E) 138 cm 
A) 90 cm 
B) 102 cm 
C) 114 cm 
D) 126 cm 
E) 138 cm

Question 19

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 20

A convex spherical mirror with a radius of 50 cm has a 4.0 cm tall object placed 100 cm in front of it.What is the position of the image relative to the mirror?

Accepted Answer

A) 20 cm behind the mirror 
B) 25 cm behind the mirror 
C) 100 cm in front of the mirror 
D) 25 cm in front of the mirror 
E) 20 cm in front of the mirror 
A) 20 cm behind the mirror 
B) 25 cm behind the mirror 
C) 100 cm in front of the mirror 
D) 25 cm in front of the mirror 
E) 20 cm in front of the mirror

Exam 34: Ray Optics

A convex lens has focal length f.If an object is located extremely far from the lens (at infinity),the image formed is located what distance from the lens?

A concave spherical mirror with a radius of 20 cm creates a real image 30 cm from the mirror.How far is the object from the mirror?

Suppose you place your face in front of a concave mirror.Which one of the following statements is correct?

It is desired to project the image of an object four times its actual size using a lens of focal length 20 cm.How far from the lens should the object be placed?

A ray of light passes from glass into a liquid,as shown in the figure.What is the speed of the light in the liquid? (c = 3.00 × 108 m/s)

In the figure,the thin lens forms a real image of the object 94.0 cm from the object.What is the focal length of the lens?

A convex spherical mirror with a focal length of magnitude 25 cm has a 4.0-cm tall flower placed 100 cm in front of it.What is the height of the image of the flower?

A compound lens is made by joining the plane surfaces of two thin plano-convex lenses of different glasses.The radius of curvature of each convex surface is 80 cm.The indices of refraction of the two glasses are 1.50 and 1.60.What is the focal length of the compound lens?

A ray of light strikes a boundary between two transparent materials,and there is no transmitted ray,as shown in the figure.What can you conclude about the indices of refraction of these two materials?

A lens is made with a focal length of -40 cm using a material with index of refraction 1.50.A second lens is made with the SAME GEOMETRY as the first lens,but using a material having refractive index of 2.00.What is the focal length of the second lens?

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?

As you walk away from a vertical plane mirror,your image in the mirror

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

A convex spherical mirror with a radius of 50 cm has a 4.0 cm tall object placed 100 cm in front of it.What is the position of the image relative to the mirror?

Concepts of Motion

Kinematics in One Dimension

Vectors and Coordinate Systems

Kinematics in Two Dimensions

Force and Motion

Dynamics I: Motion Along a Line

Newtons Third Law

Dynamics II: Motion in a Plane

Work and Kinetic Energy

Interactions and Potential Energy

Impulse and Momentum

Rotation of a Rigid Body

Newtons Theory of Gravity

Fluids and Elasticity

Oscillations

Traveling Waves

Superposition

A Macroscopic Description of Matter

Work, heat, and the First Law of Thermodynamics

The Micromacro Connection

Heat Engines and Refrigerators

Electric Charges and Forces

The Electric Field

Gausss Law

The Electric Potential

Potential and Field

Current and Resistance

Fundamentals of Circuits

The Magnetic Field

Electromagnetic Induction

Electromagnetic Fields and Waves

Ac Circuits

Wave Optics

Optical Instruments

Relativity

The Foundations of Modern Physics

Quantization

Wave Functions and Uncertainty

One-Dimensional Quantum Mechanics

Atomic Physics

Nuclear Physics

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A ray of light passes from glass into a liquid,as shown in the figure.What is the speed of the light in the liquid? (c = 3.00 × 10⁸ m/s)