Question 1

A lens with a focal length of 20 cm has what power?

Accepted Answer

A) 5.0 diopters 
B) 0.2 diopters 
C) 2 diopters 
D) -5.0 diopters 
E) 0.02​ diopters 
A) 5.0 diopters 
B) 0.2 diopters 
C) 2 diopters 
D) -5.0 diopters 
E) 0.02​ diopters

Question 2

A person's prescription for bifocals is -0.35 diopter for distant vision and +3.10 diopters for near vision,the near vision being accomplished by inserts into the distant vision lens.What is the net power of the near vision correction?

Accepted Answer

A) 2.75 diopters 
B) 3.10 diopters 
C) 3.45 diopters 
D) 1.085 diopters 
E) ​More information is needed. 
A) 2.75 diopters 
B) 3.10 diopters 
C) 3.45 diopters 
D) 1.085 diopters 
E) ​More information is needed.

Question 3

Which term below identifies the eye defect characterized by an inability to see distant objects clearly?

Accepted Answer

A) myopia 
B) presbyopia 
C) hyperopia 
D) astigmatism 
A) myopia 
B) presbyopia 
C) hyperopia 
D) astigmatism

Question 4

The ciliary muscle of the eye is relaxed under which condition?

Accepted Answer

A) eye is focused on a distant object 
B) eye is focused on a nearby object 
C) subject being viewed is well illuminated 
D) subject being viewed is dimly illuminated 
A) eye is focused on a distant object 
B) eye is focused on a nearby object 
C) subject being viewed is well illuminated 
D) subject being viewed is dimly illuminated

Question 5

A refracting astronomical telescope has objective and eyepiece lenses of focal lengths 30.0 cm and 0.40 cm,respectively.What is the angular magnification of this instrument?

Accepted Answer

A) 25 
B) 49 
C) 75 
D) 143 
E) ​30.4 
A) 25 
B) 49 
C) 75 
D) 143 
E) ​30.4

Question 6

A converging lens will be prescribed by the eye doctor to correct which of the following?

Accepted Answer

A) farsightedness 
B) glaucoma 
C) nearsightedness 
D) astigmatism 
A) farsightedness 
B) glaucoma 
C) nearsightedness 
D) astigmatism

Question 7

A person with limited accommodation is prescribed lenses of power -3.0 diopters for distant vision.Bifocal inserts are added to these lenses to allow vision at 50 cm.What is the power of the inserts?

Accepted Answer

A) -1.0 diopters 
B) 2.0 diopters 
C) 5.0 diopters 
D) 50​ diopters 
E) ​This does not work with negative diopter distance lenses. 
A) -1.0 diopters 
B) 2.0 diopters 
C) 5.0 diopters 
D) 50​ diopters 
E) ​This does not work with negative diopter distance lenses.

Question 8

When using 545-nm light,how far is the adjustable mirror of a Michelson interferometer moved when 200 fringe shifts are counted?

Accepted Answer

A) 1.36 × 10-6 m 
B) 2.73 × 10-5 m 
C) 5.45 × 10-5 m 
D) 1.36 × 10-4 m 
E) ​2.7 × 10-4 m 
A) 1.36 × 10-6 m 
B) 2.73 × 10-5 m 
C) 5.45 × 10-5 m 
D) 1.36 × 10-4 m 
E) ​2.7 × 10-4 m

Question 9

If a person is nearsighted the corrective lens will

Accepted Answer

A) take an object at the far point and form an image at 25 cm. 
B) take an object at 25 cm and form an image at the far point. 
C) take an object at infinity and form an image at the far point. 
D) take an object at infinity and form an image at 25 cm. 
A) take an object at the far point and form an image at 25 cm. 
B) take an object at 25 cm and form an image at the far point. 
C) take an object at infinity and form an image at the far point. 
D) take an object at infinity and form an image at 25 cm.

Question 10

The eye changes its f-number by

Accepted Answer

A) using the iris to change the size of the pupil. 
B) using the ciliary muscle to change the focal length of the lens. 
C) Both a & b are correct. 
D) The eye does not change its f-number. 
A) using the iris to change the size of the pupil. 
B) using the ciliary muscle to change the focal length of the lens. 
C) Both a & b are correct. 
D) The eye does not change its f-number.

Question 11

The Michelson interferometer is a device that may be used to measure

Accepted Answer

A) magnifying power of lenses. 
B) light wavelength. 
C) atomic masses. 
D) electron charge. 
A) magnifying power of lenses. 
B) light wavelength. 
C) atomic masses. 
D) electron charge.

Question 12

Find the radius of a star image formed on the retina of the eye if the aperture diameter (the pupil)at night is 0.70 cm and the length of the eye is 3.2 cm.Assume the wavelength of starlight in the eye is 500 nm.(1 nm = 10−9 m)

Accepted Answer

A) 2.8 × 10−4 m 
B) 5.6 × 10−4 m 
C) 3.1 × 10−5 m 
D) 2.8 × 10−6 m 
E) ​3.2 × 10−4 m 
A) 2.8 × 10−4 m 
B) 5.6 × 10−4 m 
C) 3.1 × 10−5 m 
D) 2.8 × 10−6 m 
E) ​3.2 × 10−4 m

Question 13

A lens is used as a magnifier.Which of the following statements is incorrect?

Accepted Answer

A) The lens is convex. 
B) The dioptric power of the lens is positive. 
C) The magnification is greatest when the eye focuses at the near point. 
D) The focal length of the lens must be negative. 
A) The lens is convex. 
B) The dioptric power of the lens is positive. 
C) The magnification is greatest when the eye focuses at the near point. 
D) The focal length of the lens must be negative.

Question 14

Quadrupling the f-number of a camera lens will change the light intensity admitted to the film by what factor?

Accepted Answer

A) 1/16 
B) 1/4 
C) 4 
D) 16 
E) ​3 
A) 1/16 
B) 1/4 
C) 4 
D) 16 
E) ​3

Question 15

If a person is farsighted the corrective lens will

Accepted Answer

A) take an object at the near point and form an image at 25 cm. 
B) take an object at 25 cm and form an image at the near point. 
C) take an object at infinity and form an image at 25 cm. 
D) take an object at infinity and form an image at the near point. 
A) take an object at the near point and form an image at 25 cm. 
B) take an object at 25 cm and form an image at the near point. 
C) take an object at infinity and form an image at 25 cm. 
D) take an object at infinity and form an image at the near point.

Question 16

A given individual is unable to see objects clearly when they are beyond 100 cm.What focal length lens should be used to correct this problem?

Accepted Answer

A) −100 cm 
B) −33.3 cm 
C) −20 cm 
D) 75 cm 
E) ​100 cm 
A) −100 cm 
B) −33.3 cm 
C) −20 cm 
D) 75 cm 
E) ​100 cm

Question 17

The ciliary muscle is instrumental in changing the shape of which eye part?

Accepted Answer

A) iris 
B) lens 
C) pupil 
D) retina 
A) iris 
B) lens 
C) pupil 
D) retina

Question 18

Tripling the focal length in a telephoto lens,while keeping the aperture size constant,will change the f-number by what factor?

Accepted Answer

A) 1/9 
B) 1/3 
C) 3 
D) 9 
E) ​1/6 
A) 1/9 
B) 1/3 
C) 3 
D) 9 
E) ​1/6

Question 19

What is the approximate magnification of a compound microscope with objective and eyepiece focal lengths of 0.30 cm and 4.1 cm,respectively,and a separation between lenses of 40 cm?

Accepted Answer

A) 320 
B) 33 
C) 32 
D) 810 
E) ​7.1 
A) 320 
B) 33 
C) 32 
D) 810 
E) ​7.1

Question 20

The pupil of the eye increases in size under which condition?

Accepted Answer

A) eye is focused on a distant object 
B) eye is focused on a nearby object 
C) object viewed is dimly illuminated 
D) object viewed is well illuminated 
A) eye is focused on a distant object 
B) eye is focused on a nearby object 
C) object viewed is dimly illuminated 
D) object viewed is well illuminated

Exam 25: Optical Instruments

A lens with a focal length of 20 cm has what power?

A person's prescription for bifocals is -0.35 diopter for distant vision and +3.10 diopters for near vision,the near vision being accomplished by inserts into the distant vision lens.What is the net power of the near vision correction?

Which term below identifies the eye defect characterized by an inability to see distant objects clearly?

The ciliary muscle of the eye is relaxed under which condition?

A refracting astronomical telescope has objective and eyepiece lenses of focal lengths 30.0 cm and 0.40 cm,respectively.What is the angular magnification of this instrument?

A converging lens will be prescribed by the eye doctor to correct which of the following?

A person with limited accommodation is prescribed lenses of power -3.0 diopters for distant vision.Bifocal inserts are added to these lenses to allow vision at 50 cm.What is the power of the inserts?

When using 545-nm light,how far is the adjustable mirror of a Michelson interferometer moved when 200 fringe shifts are counted?

If a person is nearsighted the corrective lens will

The eye changes its f-number by

The Michelson interferometer is a device that may be used to measure

Find the radius of a star image formed on the retina of the eye if the aperture diameter (the pupil)at night is 0.70 cm and the length of the eye is 3.2 cm.Assume the wavelength of starlight in the eye is 500 nm.(1 nm = 10−9 m)

A lens is used as a magnifier.Which of the following statements is incorrect?

Quadrupling the f-number of a camera lens will change the light intensity admitted to the film by what factor?

If a person is farsighted the corrective lens will

A given individual is unable to see objects clearly when they are beyond 100 cm.What focal length lens should be used to correct this problem?

The ciliary muscle is instrumental in changing the shape of which eye part?

Tripling the focal length in a telephoto lens,while keeping the aperture size constant,will change the f-number by what factor?

What is the approximate magnification of a compound microscope with objective and eyepiece focal lengths of 0.30 cm and 4.1 cm,respectively,and a separation between lenses of 40 cm?

The pupil of the eye increases in size under which condition?

Units, Trigonometry, and Vectors

Motion in One Dimension

Motion in Two Dimensions

Newtons Laws of Motion

Energy

Momentum, Impulse, and Collisions

Rotational Motion and Gravitation

Rotational Equilibrium and Dynamics

Fluids and Solids

Thermal Physics

Energy in Thermal Processes

The Laws of Thermodynamics

Vibrations and Waves

Sound

Electric Forces and Fields

Electrical Energy and Capacitance

Current and Resistance

Direct-Current Circuits

Magnetism

Induced Voltages and Inductance

Alternating-Current Circuits and Electromagnetic Waves

Reflection and Refraction of Light

Mirrors and Lenses

Wave Optics

Relativity

Quantum Physics

Atomic Physics

Nuclear Physics

Nuclear Energy and Elementary Particles

Filters

Find the radius of a star image formed on the retina of the eye if the aperture diameter (the pupil)at night is 0.70 cm and the length of the eye is 3.2 cm.Assume the wavelength of starlight in the eye is 500 nm.(1 nm = 10−⁹ m)