AP SSC 10th Class Physical Science Chapter 6 Solution – Refraction of Light at Curved Surfaces
Andhra Pradesh SSC 10th Class Physical Science Chapter 6 Refraction of Light at Curved Surfaces Solution for AP SSC 10th Class Physics/Chemistry Exam. Lots of Students of Andhra Pradesh Board will search on internet for Andhra Pradesh Class 10 Physical Science Textbook Solution or Study Material for AP SSC 10th exam. Here you search will end! Here in this page we have provided for all question answer for Chapter 6 Refraction of Light at Curved Surfaces.
For any help regarding extra notes for AP SSC 10th Class Physics/Chemistry Chapter 6 Refraction of Light at Curved Surfaces you can comment us at comment box below.
AP 10th Class Physics Chapter 6 Refraction of Light at Curved Surfaces Solution
(1) A man wants to get a picture of a zebra. He photographed a white donkey after fitting a glass, with black stripes on to the lens of his camera. What photo will he get? Explain.(AS1)
Ans: –If we use the lens if the camera with black stripes to take a photo of a zebra we will see that the photo appears with black stripes instead of clear image. This happens because of the presence of the black stripes restrict the entering of light from object.
(2) Two converging lenses are to be placed in the path of parallel rays so that the rays remain parallel after passing through both lenses. How should the lenses be arranged? Explain with a neat ray diagram. (AS1)
Ans: –
The distance between the two converging lenses when equal to the some of their focal length then we can say that the ray will be parallel to the principal axis.
(3) The focal length of a converging lens is 20cm. An object is 60cm from the lens. Where will the image be formed and what kind of image is it? (AS1)
Ans: –As we know that 1/v + 1/u = 1/f
Here, f= 20cm; u= -60
So 1/ v = 1/20 + 1/ 60.
Or v = 30cm.
The image will be real, inverted, diminished and placed 30cm away from lense.
(4) A double convex lens has two surfaces of equal radii ‘R’ and refractive index n = 15. Find the focal length ‘f’. (AS1)
Ans: –From lenses makers formula we know that 1/f = (u-1)(1/R1 – 1/R2)
Here, R1 = R2 and u=.1.5 so by applying these we get f= R
So the focal length will be equal to radius of curvature.
(5) Write the lens maker’s formula and explain the terms in it. (AS1)
Ans: –The lenses makers formula is 1/f = (u -1)( 1/ R1 – 1/R2)
Here, f÷ focal length, 1/f = power of lenses,R1, R1 radius of curvature, u= refractive index.
(6) How do you verify experimentally that the focal length of a convex lens is increased when itis kept in water? (AS1)
Ans: –From lenses makers formula we came to know that the focal length is inversely proportional to refractive index. As the refractive index of water is higher than the air we can say that the focal length will be increased.
(7) How do you find the focal length of a lens experimentally? (AS1)
Ans: –It’s considered that the light rays are parallel to each other. After converging or diverging to the focus after reflection of these parallel rays. For finding the focal length keep the convex lense on the lense holder at distance of 5cm according to meter scale from the object. Take a white screen behind the lense. Move the screen to different distance to get inverted image of the object. Now mark the point where you see the images. Then find the difference between the lense mark and screen marks to get the focal length.
(8) Harsha tells Siddhu that the double convex lens behaves like a convergent lens. But Siddhu knows that Harsha’s assertion is wrong and corrected Harsha by asking some questions. What are the questions asked by Siddhu? (AS2)
Ans:-The question that may be asked by Siddhu be If the refractive index of outside is greater than in then what will happen
- If it kept between pole and focus then how will it behave?
(9) Assertion (A): A person standing on the land appears taller than his actual height to a fishinside a pond. (AS2)
Reason (R): Light bends away from the normal as it enters air from water. Which of the following is correct? Explain.
Ans: -(a) Both A and R are true and R is write explanation of A. As we know when light passes through denser to rarer medium in bends away from normal line as a result of that this happen.
(10) A convex lens is made up of three different materials as shown in the figure
Q-10. How many of images does it form? (AS2)
Ans: –As there are three different material in the convex lenses three different image will form. The three different material have different refractive index as a result of that different image will formed.
(11) Can a virtual image be photographed by a camera? (AS2)
Ans: –Virtual image will be formed by using the camera as being imaginary light the rays do not intersect at focus. This virtual image be photographed by convex and plane mirror and concave lense.
(12) You have a lens. Suggest an experiment to find out the focal length of the lens.(AS3)
Ans: –For this experiment take a white screen behind the lense. Now placed the screen at different position to get a sharp and diminished image. And then mark the point where you get the images. Calculate the difference between the lense mark and screen mark which you pointed out then you can find the focal length.
(13) Let us assume a system that consists of two lenses with focal length f1and f2 respectively. How do you find the focal length of the system experimentally, when?
(i) two lenses are touching each other
(ii) they are separated by a distance ‘d’ with common principal axis. (AS3)
Ans: –
(14) Collect the information about the lenses available in an optical shop. Find out how the focal length of a lens may be determined by the given ‘power’ of the lens. (AS4)
Ans: –There are various types of lenses are present in a store of optical shop according to the different type uses which are Plano convex lens, Plano concave lens, double Plano concave lens, cylindrical lens etc. As we know that the power of the lenses measure by diopter (D). This 1D mean one lens can focus up to 1m of 100 cm. So to find the focal length we apply f = 100cm / Power.
(15) Collect the information about lenses used by Galileo in his telescope. (AS4)
Ans: –The objective lense was convex in nature and the eyepiece was concave. But today’s telescope uses two convex lense.
- Use the data obtained by activity-2 in table-1 of this lesson and draw the graphs of u vs v and 1/u vs 1/v. (AS5)
Ans: –
(17) Figure Q-17 shows ray AB that has passed through a divergent lens. Construct the path of the ray up to the lens if the position of its foci is known. (AS5)
Ans:-
(18) Figure Q-18 shows a point light source and its image produced by a lens with an optical axis N1 N2. Find the position of the lens and its foci using a ray diagram. (AS5)
Ans:-
(19) Find the focus by drawing a ray diagram using the position of source S and the image S/ given in the figure Q-19. (AS5)
Ans:-
(20) A parallel beam of rays is incident on a convergent lens with a focal length of 40cm. Where a divergent lens with a focal length of 15 cm should be placed for the beam of rays to remain parallel after passing through the two lenses? Draw a ray diagram. (AS5)
Ans:-
(21) Draw ray diagrams for the following positions and explain the nature and position of image.
(i) Object is placed at C2
(ii) Object is placed between F2 and optic centre P. (AS5).
Ans:
The image will be virtual, erect and enlarged.
(22) How do you appreciate the coincidence of the experimental facts with the results obtained by a ray diagram in terms of behavior of images formed by lenses? (AS6)
Ans:-We appreciate the coincidence of the experimental facts with the results obtained by a ray diagram in terms of behavior of images formed by lenses –
- With the help of ray diagram we can see the image from by telescope and microscope.
- Easily we can find the characteristics of images by using ray diagram.
- We can easily calculate the position and its property as we know the focal length of a lense.
(23) Find the refractive index of the glass which is a symmetrical convergent lens if its focal length is equal to the radius of curvature of its surface.
Ans:-From lense makers formula 1/f= (n-1)(1/R1 – 1/R2)
Here, f=R and R1=R; R2= -R; n=?
Then putting this value in the equation we get,.
1/R = (n-1) (1/R + 1/R) ; 1/R = R/2(n-1). ; n= 3/2 =1.5
So the refractive index is 1.5.
(24) Find the radii of curvature of a convexo –concave convergent lens made of glass with refractive index n=1.5 having focal length of 24cm. One of the radii of curvature is double the other. (AS7)
Ans:-From lense makers formula 1/f= (n-1)(1/R1 + 1/ R2)
Here, f= 24 and n= 1.5; R1=R and R2= 2R. By putting this value in the equation we get, 1/24= (1.5-1)(1/R – 1/2R). Or R= 6
So R1= 6 and R2 = 12.
(25) The distance between two point sources of light is 24cm .Where should a convergent lens with a focal length of f = 9cm be placed between them to obtain the images of both sources at the same point? (AS7)
Ans: – Let x be the distance between the first object. So u = 24- x as the total distance is 24cm. From the lense formula 1/f= 1/v + 1/u
Here f= 9;
For the first object the equation according to lens formula be 1/ 9 = 1/v + 1/u,
For the second object the equation will be. 1/9 = 1/-v + 1/24 -x
By solving these two equation we get x= 6. 18.
So the lense must be placed at 6cm or 18cm distance from the first object to obtain the images of both sources at the same point.
(26) Suppose you are inside the water in a swimming pool near an edge. A friend is standing on the edge. Do you find your friend taller or shorter than his usual height? Why?(AS7)
Ans: –From inside the swimming pool if i see my friend, I will see him taller than usual because of the difference of refractive index. As we all are familiar with this that when lights rays passes through denser to rarer medium we see the images slightly bends away from the normal.
FILL IN THE BLANKS
(1) The rays from the distant object, falling on the convex lens pass through …focus………….
(2) The ray passing through the ……. optical centre……………….. Of the lens is not deviated.
(3) Lens formula is given by …1/f =1/ v +1/u…………..
(4) The focal length of the Plano convex lens is 2R where R is the radius of curvature of the surface. Then the refractive index of the material of the lens is……..0…….
(5) The lens which can form real and virtual images is …….convex lense…………
MULTIPLE CHOICE QUESTIONS
(1)Which one of the following materials cannot be used to make a lens? : – (d) clay.
(2) Which of the following is true?:- (b) the distance of virtual image is not greater thanthe object distance for convex lens.
(3) Focal length of the Plano-convex lens is …………. when its radius of curvature of thesurface is R and n is the refractive index of the lens.-(c) f= R/(n -1).
(4) The value of the focal length of the lens is equal to the value of the image distance when the rays are: –(b) Parallel to the principal axis.
(5) Which of the following is the lens maker’s formula: –1/f = (n -1) (1/R1 – 1/R2).