Question 1

An object 2 cm high is placed 10 cm in front of a mirror. What type of mirror and what radius of curvature is needed for an image that is inverted and 4 cm tall?

Accepted Answer

The answer of An object 2 cm high is placed...

Question 2

An object is held at a distance of 18 cm from a convex mirror creating an image that is 1/6 the object size. What is the focal length of the mirror?

Accepted Answer

The correct answer is A because the formula for the focal length of a convex mirror is f = -d_i * d_o / (d_i - d_o), where d_i is the distance of the object from the mirror and d_o is the distance of the image from the mirror. In this case, d_i = 18 cm and d_o = 18 cm / 6 = 3 cm, so f = -18 cm * 3 cm / (18 cm - 3 cm) = -6 cm.

Question 3

An object is 12.0 cm from the surface of a spherical Christmas tree ornament that is 10.0 cm in diameter. What is the magnification of the image?

Accepted Answer

The magnification of the image is given by the equation:$$m = - \frac{d_i}{d_o}$$where $d_i$ is the image distance and $d_o$ is the object distance.In this case, the object distance is 12.0 cm and the image distance is 10.0 cm. Therefore, the magnification is:$$m = - \frac{10.0 cm}{12.0 cm} = -0.833$$The negative sign indicates that the image is virtual and upright.

Question 4

A girl is standing in front of a concave mirror. Consider two rays of light, one from her nose and one from her mouth that are parallel as they are traveling toward the mirror. These rays will come together:

Accepted Answer

When parallel rays of light enter a concave mirror, they will converge and meet at a single point called the focal point. Therefore, the two rays of light from the girl's nose and mouth will also meet at the focal point of the concave mirror. Option B is incorrect because the center of curvature is the point at the center of the mirror's curvature, and the rays will converge before getting there. Option C is also incorrect because the image point is the point where the reflected rays converge after bouncing off the mirror, but in this case, the rays have not yet been reflected. Option D is incorrect because the rays are parallel, so they will not form a virtual image behind the mirror.

Question 5

A candle is 49.0 cm in front of a concave spherical mirror of radius of curvature 70.0 cm. What are the image distance and the magnification, respectively?

Accepted Answer

The answer of A candle is 49.0 cm in front...

Question 6

A convex mirror with focal length of -20 cm forms an image 15 cm behind the surface. Where is the object located as measured from the surface?

Accepted Answer

The answer of A convex mirror with focal length of...

Question 7

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

Accepted Answer

A concave mirror can produce both real and virtual images depending on the position of the object relative to the focal point.

Question 8

A convex mirror with a focal length of -20 cm forms an image 12 cm behind the surface. If the object height is 1.2 cm what is the image height?

Accepted Answer

The mirror formula for a convex mirror is 1/f = 1/v + 1/u. Given f = -20 cm and v = -12 cm, we find u using the formula. Then, using the magnification formula m = -v/u = h'/h, where h is the object height and h' is the image height, we calculate h'.

Question 9

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

Accepted Answer

A convex mirror always forms a virtual, upright, and reduced image regardless of the object's distance from the mirror.

Question 10

If an optical system consists only of an object and a single convex mirror,

Accepted Answer

A convex mirror always forms a virtual image, which means the image is always upright and located behind the mirror. The magnification of a convex mirror is always less than one, so it cannot have an absolute value greater than 1. Additionally, the image distance can be positive or negative depending on the location of the object, but it will never be zero.

Question 11

An object placed 12 cm from a concave mirror produces a real image 8.0 cm from the mirror. If the object is now moved to a new position 15.0 cm from the mirror, where is the new image located as measured from the mirror?

Accepted Answer

Using the mirror formula:
1/v - 1/u = 1/f
where 
v is the image distance from the mirror
u is the object distance from the mirror
f is the focal length of the mirror

For the first case, u = 12 cm, v = 8 cm
1/8 - 1/12 = 1/f
f = -24 cm (negative sign indicates concave mirror)

For the second case, u = 15 cm, f = -24 cm
1/v - 1/u = 1/f
1/v - 1/15 = -1/24
v = 7.1 cm

Therefore, the new image is located 7.1 cm from the mirror, so the best choice is C.

Question 12

An object is placed 10 cm in front of a mirror, and an image is formed that has a magnification of 2.5. Which of the following statements is true?

Accepted Answer

The answer of An object is placed 10 cm in...

Question 13

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

When an object is placed closer to a concave mirror than its focal point, the image formed is virtual, upright, and magnified.

Question 14

If a virtual image is formed 8.00 cm along the principal axis from a convex mirror of focal length -15.0 cm, how far is the object from the mirror?

Accepted Answer

The answer of If a virtual image is formed 8.00...

Question 15

Parallel rays of light that hit a concave mirror will come together:

Accepted Answer

Parallel rays of light that hit a concave mirror converge at the focal point, which is the point where the rays meet after reflection.

Question 16

Which best describes the image of a concave mirror when the object is located somewhere between the focal point and twice the focal point distance from the mirror?

Accepted Answer

When an object is placed between the focal point and twice the focal point distance (center of curvature) of a concave mirror, the image formed is real, inverted, and magnified (greater than one).

Question 17

An object is placed 10 cm in front of a mirror, and an image is formed that has a magnification of 3. Which of the following statements is false?

Accepted Answer

The answer of An object is placed 10 cm in...

Question 18

Which of the following best describes the image of a concave mirror when the object is at a distance greater than twice the focal point distance from the mirror?

Accepted Answer

When an object is placed at a distance greater than twice the focal length from a concave mirror, the image formed is real, inverted, and smaller than the object, which means its magnification is less than one.

Question 19

A woman looking in a makeup mirror sees her face at twice its actual size and right-side up. If she is 22.0 cm from the mirror, what is its focal length?

Accepted Answer

The answer of A woman looking in a makeup mirror...

Question 20

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

Accepted Answer

A convex mirror always forms a virtual image, which is smaller than the actual object.

Quiz 24: Geometrical Optics

An object 2 cm high is placed 10 cm in front of a mirror. What type of mirror and what radius of curvature is needed for an image that is inverted and 4 cm tall?

An object is held at a distance of 18 cm from a convex mirror creating an image that is 1/6 the object size. What is the focal length of the mirror?

An object is 12.0 cm from the surface of a spherical Christmas tree ornament that is 10.0 cm in diameter. What is the magnification of the image?

A girl is standing in front of a concave mirror. Consider two rays of light, one from her nose and one from her mouth that are parallel as they are traveling toward the mirror. These rays will come together:

A candle is 49.0 cm in front of a concave spherical mirror of radius of curvature 70.0 cm. What are the image distance and the magnification, respectively?

A convex mirror with focal length of -20 cm forms an image 15 cm behind the surface. Where is the object located as measured from the surface?

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

A convex mirror with a focal length of -20 cm forms an image 12 cm behind the surface. If the object height is 1.2 cm what is the image height?

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

If an optical system consists only of an object and a single convex mirror,

An object placed 12 cm from a concave mirror produces a real image 8.0 cm from the mirror. If the object is now moved to a new position 15.0 cm from the mirror, where is the new image located as measured from the mirror?

An object is placed 10 cm in front of a mirror, and an image is formed that has a magnification of 2.5. Which of the following statements is true?

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?

If a virtual image is formed 8.00 cm along the principal axis from a convex mirror of focal length -15.0 cm, how far is the object from the mirror?

Parallel rays of light that hit a concave mirror will come together:

Which best describes the image of a concave mirror when the object is located somewhere between the focal point and twice the focal point distance from the mirror?

An object is placed 10 cm in front of a mirror, and an image is formed that has a magnification of 3. Which of the following statements is false?

Which of the following best describes the image of a concave mirror when the object is at a distance greater than twice the focal point distance from the mirror?

A woman looking in a makeup mirror sees her face at twice its actual size and right-side up. If she is 22.0 cm from the mirror, what is its focal length?

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