PH 202

Quiz # 07 (10 pts)

Name

Solution

 

A man is preening 1.70 m in front of a plane mirror.� Which of the following best describes the image formed by the plane mirror?

 

A.

The image of the man is formed 1.70 m in front of the mirror and is a real image.

 

 

B.

The image of the man is formed 1.70 m in front of the mirror and is a virtual image.

 

 

C.

The image of the man is formed 1.70 m behind the mirror and is a real image.

 

 

D.

The image of the man is formed 1.70 m behind the mirror and is a virtual image.

 

The image forms behind the mirror since the law of reflection holds.� The image is virtual since the light rays do not really come to a focus behind the mirror but only appear to form there.� If you were behind the mirror, you would not see the image.� So it is virtual.

 

So Correct Answer is D !

 

Light rays travel from an object very far away from a concave mirror, which has a radius of curvature .� After the rays strike the mirror, an image is formed which can best be described as:

 

A.

The image is formed at �in front of the mirror and is upright.

 

 

B.

The image is formed at �in front of the mirror and is inverted.

 

 

C.

The image is formed at �in front of the mirror and is inverted.

 

 

D.

The image is formed at �in front of the mirror and is upright.

 

The image being very far away means its object distance is infinity .� Thus the image will form at the focal length of the mirror which is one half the radius of curvature or

 

 

It is a real image so it will be inverted.

 

There was a typo obviously 23 is not 28.� So All answers were considered correct.� The intent was answer C would be correct in that the image would be in front of mirror, real and inverted.� Again, this question is scored correct for all who took the quiz.

 

A �tall object is located �to the left of a concave spherical mirror whose focal length is .� Which of the following best describes the image formed by the mirror?

 

A.

�to the left of the mirror and inverted.

 

 

B.

�to the left of the mirror and upright.

 

 

C.

�to the right of the mirror and upright.

 

 

D.

�to the right of the mirror and inverted.

 

 

 

 

This is a real image so it will be to the left of the mirror and inverted

 

So Correct Answer is A !

 

An object �tall sits on the left side of a convex spherical mirror whose radius of curvature is .� The image is formed to the right of the mirror.� How far away was the object?

 

A.

B.

C.

 

D.

 

 

 

 

 

So the Correct Answer is B !

 

An object is �tall and is located �to the left of a concave spherical mirror with a focal length of .� The image is found to be �to the left of the spherical mirror.� How tall is the image and is it upright or inverted?

 

A.

C.

 

 

 

 

B.

D.

 

Solving for the image height

 

 

- sign indicates inverted!

 

So Correct answer is A !

 

 

 

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This page last updated on October 23, 2020