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Asked by Mukul rawat

Sep 17, 2014

Find the value?

Find the value of 1/27 r3 - s3 + 125 t3 +  5 rst, if s = (r /3) + (5t).

Answers(42)

Answer

Syeda

Member since Jan 25, 2017

Answer.

* as a maccup or a shaving mirror
* as a reflectors in headlights of cars
* as a surveillance mirror in departmental stores

GRETEL GEORGE

Member since

Uses of Concave Mirrors:
It is used in front lights of cars to reflect the light.
It is used in the solar ovens and the solar furnaces to collect a large amount of solar energy in the focus of the mirror for cooking food , heating water , recharging power backups or melting metals respectively .
It is also used in A.T.M ' s to know what is going on behind you for safety reasons 

Piyush

Member since

To reflect all sides

Kirti Sharma

Member since

Uses of concave mirror-
1. It is used while putting on make up ,and in shaving mirrors
2.It is used in ATM's
3.It is used as a dentist's mirror for examination

Fousheed

Member since

Xubrixb

Mugash

Member since

It is used in oarking place

Udit

Member since

Search on your internet

Shubhi shyam

Member since

Uses of concave mirror :-
* They are used in the reflectors of torches.
* They are used in the headlights of vehicles.
* They are used by doctors and dentists to examine their patients

Shubhi shyam

Member since

Uses of concave mirror They are used in the reflectors of torches They are used in the headlights of vehicles They are used by doctors and dentists to examine their patients

Kazi hasanat

Member since

They are used as looking glass They are used for making instruments like periscope and kaleidoscope They are used on stage to create illusions and effects

Yoga

Member since

Hggfawfvr

Rithika

Member since

Concave mirror is:- -used by dentists -used as shaving mirror -used in torches and headlights to get parallel beam of light.

Anisha

Member since

Concave mirror are used as reflectors in automobile headlights. Concave mirrors are used by E.N.T. surgeons to reflect light in the inaccessible parts of ear, nose or throat. Concave mirrors are used in microscope to reflect light on to the objects to be viewed by it

ThiyagarajanP P

Member since

Not applicable

Meryem

Member since

Concave mirror are used in: ●as shaving mirror or while putting make up becoz when the object is very near it appears very big ●as a dentist's mirror used foror examination ●used in solar powered projects where they reflect the heat rays of the sun so that the rays are concentrated to a small area as they can focus a parallel beam of light to a point

Kacharia

Member since Jul 8, 2015

* as a maccup or a shaving mirror
* as a reflectors in headlights of cars
* as a surveillance mirror in departmental stores


take help :- light-reflection-and-refraction-chapter

Vikas

Member since

1) used as refractor in torches 2) used in telescopes 3) used by dentists to view a larger image of teeth

Rafay Khan

Member since

Concave lens are used to correct sightedness.they are used in eyepieces of microbes.

Ayush Singh

Member since

we use concave mirror for many purposes. they are: * as a maccup or a shaving mirror * as a reflectors in headlights of cars * as a surveillance mirror in departmental stores

Mukeshwaran

Member since

Used as reflectors in car head lamps,tourches,serchlights and telescopes Used by dentists,ent doctors to focus parts to be eminished Used in s

Hepsibha Mallepally

Member since

concave mirror can foram enlarged image.
the image is always inverted and magnified

Vivek

Member since

Shaving mirror Mirror used by dentist Galio telescope

Ramesh

Member since Apr 1, 2014

Sol:

s = (r/3) + (5t)

Cubing on both sides,

(s)3 = (r/3 + 5t)3

⇒ s3 = r3/27 + 125 t3 + 3 (r/3)(5t)(r/3 + 5t)

⇒ s3 = r3/27 + 125 t3 + (5rt)(r/3 + 5t)

⇒ s3 = r3/27 + 125 t3 + 5 rst

⇒ r3/27 - s3 + 125 t3 + 5 rst = 0

Therefore, the value of 1/27 r3 - s3 + 125 t3 + 5 rst = 0.

Aditi

Member since

reflectors in torches, road reflectors,surgeons

Kanala

Member since

It is used by doctors for examining our eyes,ears,nose,throat and teeth. It is also used in solar power projects

Abhishek Agrawal

Member since

It is used as rear view mirrors in the cars

Abban

Member since

1.through concave we can see enlarged pictures 2.use in torch 3.used in atms

Abban

Member since

Uses of concave mirrmirror are 1.concave mirror is used as reflection in the automobiles 2.concave mirror used by E.N.T sur

Saurav

Member since

1. Use in torch . 2. Use in vehicles side glass . 3 Uses as mirror

Akshwathha

Member since

Concave mirror are used as reflection in automobile.

Pavan

Member since

It is used to check eyes , ears, noses. It is used by dentists It is in schools for experiments

Abhishek Roy

Member since

It is use in big malls to look at the people

Heeral Dedhia

Member since

It is also used to correct eye defect Myopia

Alvia

Member since

1) Concave mirrors are used in vehicles 2) concave mirrors are used by dentist 3) concave mirrors are used as a reflector in torch

Bharat Moon

Member since

Concave mirrors form large images of closely placed objects . Due to this property they are used as shaving mirrors and they are also used by dentists .It is also used in vehicles .

Pragnapragath

Member since

used as reflectors in automobile headlights
used in atm's
used as shaving mirror

Avinash Kumar Singh

Member since

.it is used as shaving mirror
.in astronomical telescopes to get magnified image of heavenly bodies
.it is used by dentist to see magnified image of the teeth of the patient
.

Ravi Rana

Member since

this is use to see what is happnig inside like in police station in america

Kalpesh Prabhakar

Member since

we use concave mirror for many purposes. they are:

* as a maccup or a shaving mirror
* as a reflectors in headlights of cars
* as a surveillance mirror in departmental stores

Mehar

Member since

I have listed 10 in case u want more points to write 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.

Ajadeep Sai Devavarapu

Member since

USES OF CONCAVE MIRROR:
*IT IS USED IN ATM's because what is happening back
*IT IS USED IN REFLECTORS OF TORCH.
*IT IS USED IN PARKING AREA

Amarnathreddy M

Member since Jul 9, 2013

Write any three uses of concave mirror
 
Answer:  Uses of concave mirrors: 
  1. Concave mirror are used as reflectors in automobile headlights.
  2. Concave mirrors are used by E.N.T. surgeons to reflect light in the inaccessible parts of ear, nose or throat.
  3. Concave mirrors are used in microscope  to reflect light on to the objects to be viewed by it
 
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