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Shrish Vaidya
Subject: Science
, asked on 27/2/18
Answer the 4th question. plzzzzz no links
4.
When a concave mirror is placed facing the Sun, the Sun's rays coverage to a point 10 cm from the mirror. Now, if you place 2 cm long candles flame 20 cm away on the principal axis of the mirror, where would you place a screen to obtain the image of the candle ? What would see the size of the image ? Draw a ray diagram to justify your asnwer .
Answer
1
Trishu
Subject: Science
, asked on 27/2/18
Q. Mathematically prove that incident ray EO and emergent ray O'H are parallel. Also state that which two angles must me equal for this.
Answer
2
Rohit Patil
Subject: Science
, asked on 27/2/18
Solve this:-
Q.):- The refractive index of a medium 'x' with respect to 'y' is 2/3 and the refractive index of medium 'y' with respect to 'z' is 4/3. Calculate the refractive index of medium 'z' with respect to 'x'.
Answer
2
अर्कज ..
Subject: Science
, asked on 27/2/18
Solve this:
Answer
2
Siddhi
Subject: Science
, asked on 27/2/18
a student takes a mirror which is depressed at the centre and mounts it on a mirror stand. An erect and enlarged image of his face is formed. He places the mirror on a stand along a meter scale at 10 cm mark. In front of this mirror,he mounts a white screen and moves it back and forth along the meter scale till a highly sharp well defined image of a distant building is formed on the screen at 25.5cm mark
what is meant by depressed at centre?
what is meant by highly sharp image?
name the mirror and find its focal length
why does the student get sharp image of distant building at 25.5 mark?
Answer
1
Raghav Agrawal
Subject: Science
, asked on 26/2/18
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Answer
1
Champ Jee
Subject: Science
, asked on 26/2/18
Experts, this is like application question in my mind...
Q. I have an aquarium at my home. When i see the aquarium from front, I don't fell the fishes are distorted but when i see from above the fishes seem to be refracted. My question is why from there is refraction but not when from front? Pls clear my doubt....
Answer
3
Raghav Singh
Subject: Science
, asked on 25/2/18
2. List out the factors on which refractive index of a medium depends.
3. Under what conditions there won't be any refraction of light, when it enters from one medium to another?
Answer
1
Raghav Singh
Subject: Science
, asked on 25/2/18
In question 11,why we took u=-50? If we look at the question its saying that the image is formed at the screen 50cm from the mirror, so v=50 must be taken....
Answer
1
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question number 23.
Q.23. What is meant by refractive index? If the speed of light in a medium is 2/3 rd of the speed of light in vacuum, find the refractive index of that medium.
Answer
2
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question number 33.
Q.33. An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at distance of 32 cm from the object it is found that a distinct image of the object is formed on the screen. What is the focal length of the convex lens and size of the image formed on the screen? Draw a ray diagram to show the formation of the image in this position of the object with respect to the lens.
Answer
2
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question number 32.
Q.32. A ray of light travelling in air falls on the surface of a transparent slab. The ray makes an angle of 60
°
with the horizontal to the surface. Find the angle made by the refracted ray with the normal within the slab. (Refractive index of the material of the slab =
2
)
Answer
1
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question number 31.
Q.31. A ray of light enters a diamond from air. If the refractive index of diamond is 2.42, what % (per cent) is speed of light in diamond with that of speed in air?
Answer
1
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question 41.
Q.41. State the laws of refraction of light. Write an expression to relate absolute refractive index of a medium with speed of light in vacuum.
The refractive index of a medium x with respect to y is 2/3 and the refractive index of medium y with respect to z is 4/3. Calculate the refractive index of medium z with respect to x.
Answer
1
Raghav Singh
Subject: Science
, asked on 25/2/18
Please answer question 43.
Q.43. State the precautions that should be taken while doing the experiment, to determine the focal length of a concave mirror by obtaining the image of a distant object.
Answer
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What are you looking for?
Q.):- The refractive index of a medium 'x' with respect to 'y' is 2/3 and the refractive index of medium 'y' with respect to 'z' is 4/3. Calculate the refractive index of medium 'z' with respect to 'x'.
what is meant by depressed at centre?
what is meant by highly sharp image?
name the mirror and find its focal length
why does the student get sharp image of distant building at 25.5 mark?
Q. I have an aquarium at my home. When i see the aquarium from front, I don't fell the fishes are distorted but when i see from above the fishes seem to be refracted. My question is why from there is refraction but not when from front? Pls clear my doubt....
3. Under what conditions there won't be any refraction of light, when it enters from one medium to another?
Q.23. What is meant by refractive index? If the speed of light in a medium is 2/3 rd of the speed of light in vacuum, find the refractive index of that medium.
Q.33. An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at distance of 32 cm from the object it is found that a distinct image of the object is formed on the screen. What is the focal length of the convex lens and size of the image formed on the screen? Draw a ray diagram to show the formation of the image in this position of the object with respect to the lens.
Q.32. A ray of light travelling in air falls on the surface of a transparent slab. The ray makes an angle of 60 with the horizontal to the surface. Find the angle made by the refracted ray with the normal within the slab. (Refractive index of the material of the slab = )
Q.31. A ray of light enters a diamond from air. If the refractive index of diamond is 2.42, what % (per cent) is speed of light in diamond with that of speed in air?
Q.41. State the laws of refraction of light. Write an expression to relate absolute refractive index of a medium with speed of light in vacuum.
The refractive index of a medium x with respect to y is 2/3 and the refractive index of medium y with respect to z is 4/3. Calculate the refractive index of medium z with respect to x.
Q.43. State the precautions that should be taken while doing the experiment, to determine the focal length of a concave mirror by obtaining the image of a distant object.