Question 1

An object is placed 45.0 cm to the right of a concave mirror with focal length 24.0 cm and -5.0 cm to the left of a lens with focal length -16.0 cm.Where is the image formed by both the mirror and the lens?

Accepted Answer

A)  6.67 cm to the right of the object 
B)  6.67 cm to the right of the lens 
C)  23.2 cm to the right of the lens 
D)  7.91 cm to the right of the lens 
E)  ​23.2 cm to the left of the lens

Question 2

Use of a parabolic mirror,instead of one made of a circular arc surface,can be used to reduce the occurrence of which of the following effects?

Accepted Answer

A)  spherical aberration 
B)  mirages 
C)  chromatic aberration 
D)  light scattering

Question 3

Atmospheric refraction of light rays is responsible for:

Accepted Answer

A)  spherical aberration. 
B)  mirages. 
C)  chromatic aberration. 
D)  light scattering.

Question 4

A real object is place a distance d from a converging lens.The object is then moved to a distance 2d from the converging lens.Which of the following statements is false?

Accepted Answer

A)  The image in the first case with the object at distance d can be the larger one. 
B)  The image in the second case with the object at distance 2d can be the larger one. 
C)  If both images are real,the image in the second case is smaller. 
D)  If the image in the first case is real,the image in the second case is upright.

Question 5

Two thin lenses with 15.0-cm focal lengths at are mounted at opposite ends of a 60.0-cm long tube.An object is located 66.0 cm from one end of the tube.How far from the opposite end is the final image?

Accepted Answer

A)  18.5 cm 
B)  23.8 cm 
C)  11.4 cm 
D)  40.6 cm 
E)  ​66.0 cm

Question 6

When the reflection of an object is seen in a convex mirror the image will:

Accepted Answer

A)  always be real. 
B)  always be virtual. 
C)  may be either real or virtual. 
D)  will always be enlarged.

Question 7

Which of the following best describes the image for a thin convex lens that forms whenever the object is at a distance less than one focal length from the lens?

Accepted Answer

A)  inverted,enlarged and real 
B)  upright,enlarged and virtual 
C)  upright,diminished and virtual 
D)  inverted,diminished and real

Question 8

Five thin lenses,each of focal length f,are placed in contact.What is the resulting focal length of the combination?

Accepted Answer

A)  f 
B)  5f 
C)  f/5 
D)  5/f 
E)  ​5f/6

Question 9

How large should a wall-mounted mirror be to view the upper half of one's height,h?

Accepted Answer

A)  h 
B)  h/2 
C)  h/4 
D)  The answer is not given.

Question 10

Ansel places an object 23.0 cm from a thin convex lens along the axis.If a real image forms at a distance of 14.0 cm from the lens,what is the focal length of the lens?

Accepted Answer

A)  23.0 cm 
B)  35.8 cm 
C)  14.0 cm 
D)  8.70 cm 
E)  ​9.0 cm

Question 11

When the reflection of an object is seen in a plane mirror,the distance from the mirror to the image depends on:

Accepted Answer

A)  the wavelength of light used for viewing. 
B)  the distance from the object to the mirror. 
C)  the distance of both the observer and the object to the mirror. 
D)  the size of the object.

Question 12

Which of the following best describes the image for a thin concave lens that forms whenever the magnitude of the object distance is less than that of the lens' focal length?

Accepted Answer

A)  inverted,enlarged and real 
B)  upright,enlarged and virtual 
C)  upright,diminished and virtual 
D)  inverted,diminished and real

Question 13

A real object is place to the left of a converging lens and an image forms.Then,to the right of the converging lens a diverging lens is placed.A real,inverted final image forms to the right of the diverging lens.Which of the following could give this result?

Accepted Answer

A)  An upright virtual image caused by the first lens forms between the two lenses. 
B)  An inverted real image caused by the first lens forms between the two lenses. 
C)  A real,upright image was formed by the first lens to the right of where the diverging lens is to be placed. 
D)  A real,inverted image was formed by the first lens to the right of where the diverging lens is to be placed.

Question 14

Which of the following best describes the image of a concave mirror when the object's distance from the mirror is less than the focal point distance?

Accepted Answer

A)  virtual,upright and magnification greater than one 
B)  real,inverted and magnification less than one 
C)  virtual,upright and magnification less than one 
D)  real,inverted and magnification greater than one

Question 15

A woman looking in a makeup mirror sees her face at twice its actual size and right-side up.If she is 31.0 cm from the mirror,what is its focal length?

Accepted Answer

A)  20.7 cm 
B)  62.0 cm. 
C)  15.5 cm 
D)  62.0 cm 
E)  ​31.0 cm

Question 16

An image is formed using a convex lens,the image being 15 cm past the lens.A second lens is placed 25 cm past the first lens and another image is formed,this time 10 cm past the second lens.Which of the following statements is true?

Accepted Answer

A)  The last image is inverted with regard to the original object. 
B)  The last image must be larger than the object. 
C)  The first image is virtual. 
D)  None of the above statements is true.

Question 17

A convex lens has a focal length of magnitude F.At which of the following distances from this lens would a real object give an inverted virtual image?

Accepted Answer

A)  1/2 F 
B)  2F 
C)  Any value greater than 2F. 
D)  This cannot be done with a convex lens.

Question 18

For a converging lens with two curved surfaces,the radius of curvature for both surfaces is 11 cm.If the focal length is 20 cm,what must the index of refraction be?

Accepted Answer

A)  1.3 
B)  1.6 
C)  2.6 
D)  1.7 
E)  ​1.5

Question 19

An object is 16.0 cm from the surface of a spherical Christmas tree ornament that is 8.00 cm in diameter.What is the magnification of the image?

Accepted Answer

A)  - 0.111 
B)  - 0.556 
C)  + 0.111 
D)  + 0.556 
E)  ​+ 0.333

Question 20

A concave mirror has radius R.When an object is located a distance 2R from the lens,which describes the image formed?

Accepted Answer

A)  real,inverted,diminished 
B)  real,inverted,enlarged 
C)  virtual,upright,diminished 
D)  real,inverted,of equal size

Exam 23: Mirrors and Lenses