Question 1

A convex lens has focal length f.If an object is located at "infinity" (very far away),the image formed is located at a distance from the lens

Accepted Answer

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

Question 2

Reza's face is 20 cm in front of a concave shaving mirror having a focal length of magnitude 30 cm.How large is the image of his face?

Accepted Answer

A) half as large as his face 
B) of the same size as his face 
C) twice as large as his face 
D) three times as large as his face 
E) four times as large as his face 
A) half as large as his face 
B) of the same size as his face 
C) twice as large as his face 
D) three times as large as his face 
E) four times as large as his face

Question 3

Single concave spherical mirrors produce images that

Accepted Answer

A) are always smaller than the actual object. 
B) are always larger than the actual object. 
C) are always the same size as the actual object. 
D) could be smaller than,larger than,or the same size as the actual object,depending on the placement of the object. 
E) are always real. 
A) are always smaller than the actual object. 
B) are always larger than the actual object. 
C) are always the same size as the actual object. 
D) could be smaller than,larger than,or the same size as the actual object,depending on the placement of the object. 
E) are always real.

Question 4

How far from a lens having a focal length of +50 mm must the object be placed if it is to form a virtual image that is 3.0 times the size of the object?

Accepted Answer

A) 33 mm 
B) 42 mm 
C) 48 mm 
D) 54 mm 
A) 33 mm 
B) 42 mm 
C) 48 mm 
D) 54 mm

Question 5

The focal length of a concave mirror has a magnitude of 20 cm.What is its radius of curvature?

Accepted Answer

A) 10 cm 
B) 40 cm 
C) -40 cm 
D) 20 cm 
E) -20 cm 
A) 10 cm 
B) 40 cm 
C) -40 cm 
D) 20 cm 
E) -20 cm

Question 6

Light enters air from water.The angle of refraction will be

Accepted Answer

A) greater than the angle of incidence. 
B) equal to the angle of incidence. 
C) less than the angle of incidence. 
A) greater than the angle of incidence. 
B) equal to the angle of incidence. 
C) less than the angle of incidence.

Question 7

An object is placed near a concave mirror having a radius of curvature of magnitude 60 cm.How far should you place the object from the mirror so that the lateral magnification produced by the mirror will be +2.5?

Accepted Answer

A) 18 cm 
B) 24 cm 
C) 30 cm 
D) 36 cm 
E) 42 cm 
A) 18 cm 
B) 24 cm 
C) 30 cm 
D) 36 cm 
E) 42 cm

Question 8

Suppose you wanted to start a fire using a mirror to focus sunlight.Which of the following statements is most accurate?

Accepted Answer

A) It would be best to use a plane mirror. 
B) It would be best to use a convex mirror. 
C) It would be best to use a concave mirror,with the object to be ignited positioned at the center of curvature of the mirror. 
D) It would be best to use a concave mirror,with the object to be ignited positioned halfway between the mirror and its center of curvature. 
E) One cannot start a fire using a mirror,since mirrors form only virtual images. 
A) It would be best to use a plane mirror. 
B) It would be best to use a convex mirror. 
C) It would be best to use a concave mirror,with the object to be ignited positioned at the center of curvature of the mirror. 
D) It would be best to use a concave mirror,with the object to be ignited positioned halfway between the mirror and its center of curvature. 
E) One cannot start a fire using a mirror,since mirrors form only virtual images.

Question 9

A drawing is placed 40 cm in front of a thin lens.If a virtual image forms at a distance of 50 cm from the lens,on the same side as the drawing,what is the focal length of the lens?

Accepted Answer

A) -45 cm 
B) 75 cm 
C) 90 cm 
D) 200 cm 
A) -45 cm 
B) 75 cm 
C) 90 cm 
D) 200 cm

Question 10

Which of following statements about the image formed by a single diverging lens are true? (There could be more than one correct choice. )

Accepted Answer

A) The image is always real. 
B) The image is always virtual. 
C) The image is always inverted. 
D) The image is always upright. 
E) The image is always smaller than the object. 
A) The image is always real. 
B) The image is always virtual. 
C) The image is always inverted. 
D) The image is always upright. 
E) The image is always smaller than the object.

Question 11

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

Accepted Answer

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

Question 12

During the investigation of a new type of optical fiber having an index of refraction  
A laser beam is aimed at the flat end of a straight fiber,as shown in the figure.What is the maximum angle of incidence θ1 if the beam is not to escape from the sides of the fiber if it is surrounded by air?

Accepted Answer

A) 42.9° 
B) 39.8° 
C) 36.7° 
D) 33.6° 
E) 30.5° 
A) 42.9° 
B) 39.8° 
C) 36.7° 
D) 33.6° 
E) 30.5°

Question 13

A convex lens has focal length f.If an object is placed at a distance of 2f from the lens on the principal axis,the image is located at a distance from the lens

Accepted Answer

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

Question 14

A toy is 14 cm in front of a convex spherical mirror.If the image of the toy is 5.8 cm behind the mirror,what is the focal length of the mirror?

Accepted Answer

A) -4.1 cm 
B) +20 cm 
C) -9.9 cm 
D) -20 cm 
E) +9.9 cm 
A) -4.1 cm 
B) +20 cm 
C) -9.9 cm 
D) -20 cm 
E) +9.9 cm

Question 15

You may have seen ambulances on the street with the letters of the word AMBULANCE written on the front of them,in such a way as to appear correctly when viewed in your car's rear-view mirror.(See the figure. )How do the letters appear when you look directly at the ambulance (not through the mirror)?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 16

A tank holds a layer of oil,of thickness To = 1.43 m,that floats on a layer of syrup of thickness Ts = 0.640 m,as shown in the figure.Both liquids are clear and do not mix together.A light ray,originating at the bottom of the tank at point P,crosses the oil-syrup interface at a point 0.900 m from the axis.The ray continues and arrives at the oil-air interface,2.00 m to the right of P and at the critical angle.What is the index of refraction of the oil?

Accepted Answer

A) 1.64 
B) 1.62 
C) 1.60 
D) 1.66 
E) 1.68 
A) 1.64 
B) 1.62 
C) 1.60 
D) 1.66 
E) 1.68

Question 17

A beam of light that is parallel to the principal axis strikes a concave mirror.What happens to the reflected beam of light?

Accepted Answer

A) It also is parallel to the principal axis. 
B) It is perpendicular to the principal axis. 
C) It passes through the center of curvature of the mirror. 
D) It passes through the focal point of the mirror. 
E) It passes between the focal point and the center of curvature of the mirror. 
A) It also is parallel to the principal axis. 
B) It is perpendicular to the principal axis. 
C) It passes through the center of curvature of the mirror. 
D) It passes through the focal point of the mirror. 
E) It passes between the focal point and the center of curvature of the mirror.

Question 18

A wrench is placed at 30 cm in front of a diverging lens with a focal length of magnitude 10 cm.What is the magnification of the wrench?

Accepted Answer

A) 0.25 
B) -0.25 
C) 0.67 
D) -0.67 
E) 4.0 
A) 0.25 
B) -0.25 
C) 0.67 
D) -0.67 
E) 4.0

Question 19

Lucite has an index of refraction of 1.50.What is its critical angle if it is in air?

Accepted Answer

A) 1.16° 
B) 15° 
C) 41.8° 
D) 65.2° 
E) 87.4° 
A) 1.16° 
B) 15° 
C) 41.8° 
D) 65.2° 
E) 87.4°

Question 20

Which one of the following sets of characteristics describes the image formed by a plane mirror?

Accepted Answer

A) real and inverted 
B) real and upright 
C) virtual and upright 
D) virtual and inverted 
E) virtual and larger than the object 
A) real and inverted 
B) real and upright 
C) virtual and upright 
D) virtual and inverted 
E) virtual and larger than the object

Exam 26: Geometrical Optics

A convex lens has focal length f.If an object is located at "infinity" (very far away),the image formed is located at a distance from the lens

Reza's face is 20 cm in front of a concave shaving mirror having a focal length of magnitude 30 cm.How large is the image of his face?

Single concave spherical mirrors produce images that

How far from a lens having a focal length of +50 mm must the object be placed if it is to form a virtual image that is 3.0 times the size of the object?

The focal length of a concave mirror has a magnitude of 20 cm.What is its radius of curvature?

Light enters air from water.The angle of refraction will be

An object is placed near a concave mirror having a radius of curvature of magnitude 60 cm.How far should you place the object from the mirror so that the lateral magnification produced by the mirror will be +2.5?

Suppose you wanted to start a fire using a mirror to focus sunlight.Which of the following statements is most accurate?

A drawing is placed 40 cm in front of a thin lens.If a virtual image forms at a distance of 50 cm from the lens,on the same side as the drawing,what is the focal length of the lens?

Which of following statements about the image formed by a single diverging lens are true? (There could be more than one correct choice. )

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

During the investigation of a new type of optical fiber having an index of refraction A laser beam is aimed at the flat end of a straight fiber,as shown in the figure.What is the maximum angle of incidence θ1 if the beam is not to escape from the sides of the fiber if it is surrounded by air?

A convex lens has focal length f.If an object is placed at a distance of 2f from the lens on the principal axis,the image is located at a distance from the lens

A toy is 14 cm in front of a convex spherical mirror.If the image of the toy is 5.8 cm behind the mirror,what is the focal length of the mirror?

A beam of light that is parallel to the principal axis strikes a concave mirror.What happens to the reflected beam of light?

A wrench is placed at 30 cm in front of a diverging lens with a focal length of magnitude 10 cm.What is the magnification of the wrench?

Lucite has an index of refraction of 1.50.What is its critical angle if it is in air?

Which one of the following sets of characteristics describes the image formed by a plane mirror?

Introduction to Physics

One-Dimensional Kinematics

Vectors in Physics

Two-Dimensional Kinematics

Newtons Laws of Motion

Applications of Newtons Laws

Work and Kinetic Energy

Potential Energy and Conservation of Energy

Linear Momentum and Collisions

Rotational Kinematics and Energy

Rotational Dynamics and Static Equilibrium

Gravity

Oscillations About Equilibrium

Waves and Sound

Fluids

Temperature and Heat

Phases and Phase Changes

The Laws of Thermodynamics

Electric Charges, Forces, and Fields

Electric Potential and Electric

Electric Current and Direct-Current Circuits

Magnetism

Magnetic Flux and Faradays Law of Induction

Alternating-Current Circuits

Electromagnetic Waves

Optical Instruments

Physical Optics: Interference and Diffraction

Relativity

Quantum Physics

Atomic Physics

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