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# 10 Uses of Concave Mirror

Concept:

A curved mirror is one with a curved reflective surface. It can be either convex or concave. Concave mirrors are the one that are bulging inward. It is also known as converging mirror.
The concave mirrors are called converging because as light falls on the mirror, it collects the light and refocus the parallel incoming rays. Here we will briefly explain the 10 uses of concave mirror. There can be more uses as well, but we would take up major 10 uses of concave mirror only in this section.

10 Uses Of Concave Mirror

We will now explain the major 10 uses of concave mirror below:
1. One of the important applications of a concave mirror is in satellite dishes. These antennas are designed to first receive and then amplify (increase) the weaker signals that are sent in space via communication satellites. As the distance is very large, the waves reaching the earth from the antennas are in parallel. Thus when these parallel waves strike a concave surfaced mirrored antenna dish, they all get reflected by the focus of the concave mirror. At that focus the receiver for the signals is placed. Here, the purpose of mirror is to gather weaker signals falling over a  bigger area and them concentrate or focus them on one point or spot.

2. Another major application of concave mirrors is in headlights of the car. A powerful source of light in a smaller size is placed at the focus point of the concave mirror which is placed at the back of the headlight. Then any light from the focus that will strike the mirror will get reflected in parallel to the axis of the concave mirror. Thus the beam of headlight gets focused in this way.

3. One more application of concave mirrors is in telescopes used for astronomical studies. All telescopes may them be large or small, use concave mirror in accordance to the size of the telescope. If telescope is large a bigger mirror is used, for smaller ones small mirror is used. The mirror is placed at the bottom of the telescope such that it can gather light and form a smaller image than the original size of the image on a small and plane mirror placed at the top. This plane mirror is simply placed to reflect the light into the eyepiece or camera or other output source of the telescope. Astronomers use larger mirrored telescope because it gathers more light and fainter objects can then easily be viewed.

4. Shaving mirrors are another example that makes use of concave mirrors because of their curved and reflective surface.

5. Dentist and ENT doctors also use concave mirrors in their examinations procedure to obtain a larger image than the original of teeth, ear or skin etc.

6. Concave mirrors are also used in torches on the same principle as they are used in vehicles headlights.

7. They are also used in solar powered gadgets. The parallel rays of the sun are focused at the focal point of the mirror and then the reflected rays are used for heating purposes like cooking, heating water, recharging power backups etc.

8. They are used in electron microscopes and magnifying glasses to get a larger view of smaller objects under study.

9. Another use of concave mirror is in visual bomb detectors.

10. The flash light mirror of camera also makes use of concave mirrors.

These are the 10 uses of  concave mirrors in common practice.

Question:concave mirror uses

Answers:1. headlights of cars 2. dentist's mirror 3. solar devices 4. reflecting telescopes 5. satellite dishes 6. personal uses(men shaving, women applying make-ups etc) 7. reflectors in flash-lights 8. electron microscopes

Question:My friends and I don't know how to solve this problems for our summer physics homework. Help please. Step-by-step would be great! A plane mirror and a concave mirror (f=8.0cm) are facing each other and are separated be a distance of 20.0cm. An object is placed 10.0cm in front of the plane mirror. Consider the light from the object that reflects first from the plane mirror and then from the concave mirror. Using a rad diagram drawn to scale, find the location of the image that this light produces in the concave mirror. Specify this distance relative to the concave mirror.

Answers:This is an example of what's called 'folded optics.' Here's one way to approach this problem: Ignore the concave mirror for a moment and consider yourself facing the plane mirror; what do you see? Your image as far 'behind' the plane mirror as you are in front of it? Yes! This is what the concave mirror 'sees' - the image of the object >as if< it were 10.0 cm >behind< the plane mirror. Now, to solve this problem, pretend that the plane mirror is not there at all. Pretend rather that the object itself is 10.0 cm >beyond< the plane mirror. If you know how to solve that problem, you can solve the one given. The answer will be the same. The concave mirror doesn't care either way. As far as it's concerned, the image it sees is >the one behind the mirror.< I have not done this problem for you, giving you answers in centimeters and so forth, because it is a homework problem for you to work out yourself. Were I to solve it for you, I would be cheating you out of part of your education, and that wouldn't be right, yes? So, give it a shot and let me know how it turns out, okay? Take care, -b

Question:Use the mirror equation to determine the image distance of the image formed by a 2 cm high object that is located at an object distance of 10 cm from a concave mirror that has a radius of curvature of 14 cm. Use the thin lens equation to calculate the image distance of the image formed by a 3 cm high object that is located 5 cm from a convex (converging) lens having a focal length of 4 cm.

Answers:Ok, you're given d sub o, which is 2cm, and the center, which is twice the focus, making the focus 7 cm. Using the equation 1/f = 1/d sub o + 1/d sub i, you would get your image distance, which would be 23.3 cm. You would do the same with the convex mirror, except they give you a focus, so your equation would look like 1/4 = 1/5 + 1/d sub i, making d sub i 20 cm.

Question:A concave shaving mirror has a radius of curvature of 35cm. It is positioned so that the upright image of a man's face is 2.50 times the size of the face. How far is the mirror from the face?

Answers:Let th edistance of image be v then -1/v+1/u = 1/f, multiply by v -1+2.5 = v/(35/2) or 1.5 = 2v/35 or v = (35x1.5)/2 = 26.5 cm behind the mirror or u = 26.5/25 = 10.5 cm in front of mirror.