Question 1

Two plane mirrors make an angle of 120º as shown. An object is placed at O. When the eye is placed at E, it will observe images formed at

Accepted Answer

B

Question 2

A concave spherical mirror has a radius of curvature of 50 cm. The image of an object located 35 cm in front of the mirror is

Accepted Answer

For a concave mirror, the mirror equation is $ \frac{1}{f} = \frac{1}{v} + \frac{1}{u} $, where $f$ is the focal length, $v$ is the image distance, and $u$ is the object distance. Given the radius of curvature is 50 cm, the focal length $f = \frac{R}{2} = 25$ cm. The object distance $u = -35$ cm (negative because it's in front of the mirror). Plugging these values into the mirror equation gives $ \frac{1}{25} = \frac{1}{v} - \frac{1}{35} $, solving for $v$ gives $v = 87.5$ cm, indicating the image is real and on the same side as the object (since $v$ is positive). The magnification $m = -\frac{v}{u} = -\frac{87.5}{-35} = 2.5$, indicating the image is inverted (since magnification is positive) and magnified 2.5 times.

Question 3

What is the minimum height of a plane mirror in which a standing woman can see her entire body reflected?

Accepted Answer

In a plane mirror, the image formed is at the same distance behind the mirror as the object is in front of the mirror. Therefore, in order for a standing woman to see her entire body reflected, the mirror must be tall enough to reflect her full height. Since the mirror reflects the image at the same distance behind the mirror as the object is in front of the mirror, the minimum height of the mirror must be equal to the woman's height, which is one-half her total height from head to feet. Therefore, the minimum height of the mirror must be one-half her height.

Question 4

An object is placed between two mirrors set at an angle to each other. The location of the image of the object in mirror 1 is shown in the figure. The location of the image of that image in mirror 2 is at

Accepted Answer

The answer of  An object is placed between two...

Question 5

A concave spherical mirror can produce which one of the following type of image?

Accepted Answer

A concave mirror can produce a magnified, erect, and virtual image when the object is placed between the focal point and the mirror.

Question 6

When an object is closer to a concave mirror than the mirror's focal point, the

Accepted Answer

The answer of When an object is closer to a...

Question 7

A point object P is placed before two mirrors at right angles as shown. Images of the object are formed only at positions

Accepted Answer

The answer of  A point object P is placed...

Question 8

A point object P is placed before two mirrors at right angles as shown. How many total number of images will be formed due to reflections from these mirrors?

Accepted Answer

Two mirrors at right angles will form three images. The first image (P') will be formed due to reflection from the mirror closest to the point P. This image will be at the same distance but on the opposite side of the mirror as the object. The second image (P'') will be formed due to reflection from the mirror perpendicular to the first mirror. This image will be at the same distance and on the same side of the mirror as the object. The third image (P''') will be formed due to reflection from both mirrors. This image will be at the intersection point of the mirrors and will be farther away from the mirrors than the object. Therefore, the total number of images formed will be three.

Question 9

A person of height H stands in front of a vertical plane mirror that is only half of her height. In the reflected image, this person will be able to see

Accepted Answer

A plane mirror reflects light such that the angle of incidence equals the angle of reflection. A person can see their entire body in a mirror that is half their height because the light from their feet reflects off the lower part of the mirror and reaches their eyes, while light from their head reflects off the upper part of the mirror.

Question 10

An object is placed 10 inches in front of a concave mirror that has a radius of curvature of 8 inches. The image is located

Accepted Answer

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

Question 11

Two plane mirrors are a distance 2d apart and parallel to one another. An object is placed at the midpoint between the two mirrors. After two reflections on each mirror, how far will be the image from the mirror with the last, i.e., the fourth, reflection?

Accepted Answer

The answer of Two plane mirrors are a distance 2d...

Question 12

The image of an object located 10 cm from a concave spherical mirror of radius 10 cm is

Accepted Answer

The answer of The image of an object located 10...

Question 13

The technical name for the type of image formed by a single plane mirror is

Accepted Answer

A plane mirror forms a virtual image, meaning the light rays appear to be coming from a location behind the mirror, resulting in an image that cannot be projected onto a screen. It is not a real image because the light does not actually converge to a point in front of the mirror. It is not inverted, enlarged, or focal because the image appears to be the same size as the object and at the same distance from the mirror as the object.

Question 14

An object 0.50 cm high is 5.0 cm from a concave spherical mirror of focal length 20 cm. How high is the image and is it erect or inverted?

Accepted Answer

The answer of An object 0.50 cm high is 5.0...

Question 15

When you look at the image reflected from two plane mirrors placed at 90º, the image

Accepted Answer

When two plane mirrors are placed at 90º, the image formed is a combination of two reflections, which results in an image that does not change handiness (i.e., it is not inverted like a single mirror reflection would be).

Question 16

Two plane mirrors are arranged so that the reflecting surfaces face each other and are parallel. The mirrors are located at x = -2 m and x = 2 m. An object is located at x = 1 m. The second image from the left mirror is located at

Accepted Answer

The first image in the left mirror is at x = -3 m (reflection of the object at x = 1 m). The second image is a reflection of this image in the right mirror, located at x = 5 m. The second image from the left mirror is a reflection of this image at x = 5 m, which is at x = -5 m.

Question 17

Two parallel rays are incident on a concave spherical mirror whose center of curvature is at 3. After being reflected, the two rays cross at point

Accepted Answer

The answer of  Two parallel rays are incident on...

Question 18

The parallel rays incident on the surface of the concave spherical mirror in the figure converge to a point at

Accepted Answer

The answer of  The parallel rays incident on the...

Question 19

Two parallel mirrors are a distance d apart. An object is placed 1.0 inch in front of the right-hand mirror. After 5 reflections, with the first reflection from the right-hand mirror, an image is located 17 inches behind the right-hand mirror. Calculate the distance between the mirrors.

Accepted Answer

The answer of Two parallel mirrors are a distance d...

Question 20

When an object is farther from a concave mirror than twice the mirror's focal length, the

Accepted Answer

When an object is placed farther than twice the focal length of a concave mirror, the image formed is real, inverted, and smaller than the object. This means the magnification is less than one, the image is inverted, and the image distance is less than the object distance, making all of these statements correct.

Quiz 24: Geometrical Optics