Question

ONLY 2 and 5 still need answers. BUT THIS IS 25 POINTS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! PLEASE ANSWER ALL PARTS. Answered all of them except 2 and 5

EDIT: I have answers 6. is X
1. is it will be larger and upright
2. I still have no idea HELP!!!!!
3. is convex and concave
4.is b
5. again no idea HELP!!!!!


1. The ray diagram shows a candle that is placed between the focal point and the mirror.
(see first image)

Which best describes the image that will be produced compared with the object?

It will be smaller and upright.
It will be smaller and inverted.
It will be larger and upright.
It will be larger and inverted.
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2. A 5.0 cm object is 12.0 cm from a concave mirror that has a focal length of 24.0 cm. The distance between the image and the mirror is _________ cm.
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3. Felix made a chart listing the uses for two types of mirrors.

(see second image)

Which headings belong in the chart?

X: Plane
Y: Convex
X: Concave
Y: Plane
X: Convex
Y: Concave
X: Convex
Y: Plane
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4. Barbara places an object in front of a mirror. The mirror produces an image that is inverted, real, and smaller than the object.

Which kind(s) of mirror could Barbara be using?

convex, because concave and plane mirrors produce only virtual images
concave, because plane and convex mirrors produce only upright virtual images
concave or convex, because both types of mirrors produce images that are inverted and real
convex or plane, because both types of mirrors produce an image that is smaller than the object
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5. A ray diagram is shown.

(see third image)

Which describes the image?

It is virtual and in front of the mirror.
It is virtual and behind the mirror.
It is real and in front of the mirror.
It is real and behind the mirror.
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6. The diagram shows how an image is produced by a plane mirror.

(see the fourth picture)
Which letter shows where the image will be produced?

W
X
Y
Z

Answer 1

1) the correct answer is
"It will be larger and upright."

Let's see why. By looking at the green and purple rays, we can see that they diverge on the left, so they never meet on the left. Therefore we should prolong them to the right, behind the mirror (see attached figure) and if we do that, we can see that they meet at some point at the same height of the green ray. This means that the image is larger than the original object, and also upright.

2) the distance between the image and the mirror is 24 cm.
We can solve the problem by using the mirror equation:

`(1)/(f)= (1)/(d_o)+ (1)/(d_i)`
where f is the focal length,
`d_o` the distance of the object from the mirror,
`d_i` the distance of the image from the mirror.

We must also be careful to use the right sign convention. For a concave mirror, the focal length is taken as positive, so f=+24.0 cm, and
`d_o = 12.0cm`. By solving the equation, we find

`(1)/(d_i) = (1)/(f)- (1)/(d_o)= (1)/(24 cm)- (1)/(12 cm)=- (1)/(24 cm)`
from which we have

`d_i=-24 cm`
so, the image is located 24 cm from the mirror, behind it (because of the negative sign, that tells us that the image is virtual)

3) The right answer is :
X --> convex
Y --> concave

Why that? the reason is the following: the image produced by convex mirrors is always smaller than the original object. This also means that convex mirrors can cover a wide field of view, so they are particularly usefule as side mirrors in the car or to see traffic around blind corners.
Vice-versa, concave mirrors can produce images larger than the original objects, so they are used in dental instruments (to enlarge what there is inside the mouth) or in telescope (to enlarge the image of the planets or celestial objects).

4) The correct answer is:
"concave, because plane and convex mirrors produce only upright virtual images"
In fact, images produced by convex mirrors are always virtual, as well the images produced by a plane mirror, while concave mirrors can produce both real and virtual images, depending on the distance of the object from the mirror. Since in this example the image produced by the mirror is real, the mirror can only be concave.

5) The correct answer is:
"It is virtual and behind the mirror."

In fact, the image is located on the right of the mirror, so on the opposite side with respect to the real object: this means that the image is virtual, i.e. located behind the mirror.

6) Correct answer is: X.

To see where the image is located, we must prolong the ray that goes from Z (the eye) to the mirror, and then prolonging it behind the mirror we can see that at some point it reaches X, and this is exactly where the image is located.

Answer 2

Answers are:
(1) The correct option is (C): It will be larger and upright.
(2) Image distance = -24cm (The negative sign indicates that the resultant image will be virtual: meaning the image formed using the apparent divergence of rays)
(3) the correct combination is (C): X: Convex Y: Concave
(4) The correct option is (B) concave, because plane and convex mirrors produce only upright virtual images
(5) The correct option is (B) It is virtual and behind the mirror.
(6) The correct option is (B): X

Explanations:
(1): The image shows that the object (in this case it's candle) is in between the focal point and the mirror itself. In this case the one ray which is parallel to the mirror axis will pass through the focal point where as the second ray will first pass through the focal point and then touches the tip of the candle. If we extend the two rays behind the mirror, we will get the larger and upright image behind the mirror (as shown in the image attached with this post). Hence correct option is (C): It will be larger and upright.

ALWAYS REMEMBER: When the mirror is concave, and the object is in-between the focal point and the mirror itself, the resultant image will be virtual ( meaning the image formed using the apparent divergence of rays), larger and upright!


(2): Since it is the concave mirror, the focal length has to be positive.
According to mirror formula:
1 / (focal-length) = (1 / object-distance) + (1 / image-distance)
1 / 24 = 1/12 + (1/image-distance)
image-distance = -24cm (The negative sign indicates that the resultant image will be virtual: meaning the image formed using the apparent divergence of rays)

(3): Convex mirrors are used as side view mirrors on cars and to help people see traffic around blind corners because those mirror bend light upon its reflection making the resultant image smaller which helps us to fit more image onto the mirror. Whereas, concave mirrors are used to magnify the image as in telescopes and dental instruments. Hence, the correct combination is:
X: Convex
Y: Concave

(4): The correct option is (B) as concave mirrors produces inverted, real, and smaller than the object when the object is behind the focal point of the mirror while in the case of plane and convex mirrors, they produce only upright virtual images in that specific case.

(5): As you can see in the image-attached, the resultant image is formed by using the apparent divergence of ray(dotted lines), the image is virtual and formed behind the mirror. Hence the correct option is (B) It is virtual and behind the mirror.

(6): In case of plane mirrors, the image is formed behind the mirror (because the resultant image is virtual) and would have the same size and axis as original. As we can see in the image-attached in question, X is the location which is behind the mirror and is in same axis as the original object. Hence the correct option is (B): X