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write 3 difference between concave and convex lens?
write 3 differences between real and virtual images?
The magnification m of an image formed by a spherical mirror is negative . it means the image is a) smaller than the object b) larger than the objectc) erect d) inverted
The magnification m of an image formed by a spherical mirror is negative . it means the image is
a) smaller than the object
b) larger than the object
c) erect d) inverted
What is meant by lateral displacement?
What is the meaning of virtual and erect image???
A man wearing yellow coloured glass for left eye and red coloured glass for right eye stands infront of a plane mirror. He observes his image in the mirror.Which statement is correct?
(a) left eye is yellow coloured and right is red coloured
(b) left eye is red coloured and rigt eye is yellow coloured.
derivation of mirror formula as well as lens formula ?
define power of lens and gives its S.I.unit
State the Principle of reversibility of light
explain..why a pencil partly immersed in water appears to be bent at the water surface
Snell's law states that
u(constant of refraction) = sini/sinr
If a ray of light is passing through a glass slab through its normal, then sin i = 0 and thus the constant of refraction is not mantained.
But as the definition of snell's law suggests that this law is applicable to light travelling obliquely. If this is so, I have a question:
Refraction occurs due to the change in velocity of light in 2 different mediums. This change in velocity occurs as the atoms in a particular media has a specific frequency and if the light wave has a different frequecy, only then will it let the light pass through. But in this process, the light is refracted at some angle. BUT WHY DOES THIS REFRACTION NOT OCCUR WHEN LIGHT TRAVELS THROUGH THE NORMAL?
(I hope you understand the question. If not, pls tell me where I am not clear, i'll try to explain in a better way)
what is tyndall effect?
define absolute refractive index of a medium.?
WHAT IS VIRTUAL AND ERECT IMAGE
One half of a convex lens is covered with a black paper.will such a lens produce an image of the complete object?support your answer with a ray diagram.
plz ans. fast as i hv a revision test on monday
write 3 differences between reflection and refraction
an object is placed at a distance of 10 cm from a convex mirror of focal length 15cm. find the position and nature of the image.
refractive index of glass with respect to air is 3/2..refractive index of water with respect to air is 4/3..what is the refractive index of glass with respect to water?? is it 3/2 divided by4/3 or 4/3 divided by 3/2??
A parallel beam of light is made to fall on a concave mirror.An image is formed at a distance of 7.5 cm from the mirror.What are the focal length and radius of curvqature of the mirror?
a student focused the image of the candle flame on a white screen using a convex lens .He noted down the positions of the candle flame , screen and the lens as given below
position of candle flame = 12 cm
position of the lens= 50 cm
position of the screen = 88cm
Q 1 find the focal length of the convex lens.
Q 2 Find the position of the image of the candle flame if it is shifted towards the lens at a position of 31cm
Q3 State the nature of the image formned if the candle flame is further shifetd towards the lens..
this is a 10th board question n i m nt able 2 solve it plz helppppp
A lens of focal length "f" is cut into two equal parts without affecting its curvature.the two pieces will have equal focal length of : A) f. B) 2f. C) f/2. D) f/3
the history of spherical mirrors in human civilization
The speed of light in transparent medium is 0.6 times that of its speed in vacuum.what is the refractive index of the medium ?
What will happen to the focal length if the convex lens is dip inside the water.
the refractive index of diamond is 2.42 what is the meaning of this statement?
justify and explain this
its a urgent question
1- the fact that a small source of light cast a sharp shadow of an opaque object tells us that light travels in straight line path i dont understand this
2- how and why ddoes any object caste shadow
3- what is the evidence for wave nature of light as well as for particle nature of light
4- explain this line in 150 words and prove this
light is composed of particles which travels in a straight line at very high speed
what is a focal length of plane mirror
Q1. A concave lens has focal length 20cm.At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens?Also calculate the size of theimage formed.
Q2. A convex lens has a focal length of 30 cm. Calculate at what distance should the object be placed from the lens so that it forms an image at 60 cm on the other side of the lens?. Find the magnification produced by the lens in this case.
Name the type of mirror used in the following situations.
of a car
mirror of a vehicle
your answer with reason.
a concave mirror produces 3 times enlarged image of an object placed at 10 cm in front of it.Calculate radius of curvature of mirror
1.A student lying on the floor near a swimming pool wants to see an object at its bottom surface. The angle of incidence of light from the object on the surface of water is called _?
2.Theangle of deviation A of a reflected light from the incident light B is_?(180-A),(180-2A)
state snells law of refraction.
Define principal focus of a lens ?
To a fish, the plane surface of earth appears to be enclosed within an angle of
(a)600 (b)1800 (c)970 (d)450
Derive lens formula, that is 1/v - 1/u = 1/f
When a bright object os placed 10 cm away from a concave mirror, its real image is formed at a distance 40cm from the mirror. What is the focal lencgt of the mirror
what will be your observation,when an object placed in front of concave mirror,is moving towards the pole of the mirror?
The refractive index of water is 4/3 and for glass is 3/2 w.r.t air. What is the refractive index of glass w.r.t. water?
define principal focus of a Convex lens and Concave lens
define the principal focus of a convex mirror
What is tyndall effect?Explain an example
A concave mirror produces three times magnified real image of an object placed 10 cm in front of it.Where is the image located
An object is placed 12 cm away from the optical centre of a lens Its image is formed exactly midway between the optical centre and the object. Wht is the nature of lens and its focal length.
DEFINE RARER & DENSER MEDIUM.
why a convex mirror is used as rear view mirror
A student focussed the image of a candle flame
When an object is placed at a distance of 50 cm from a concave mirror , the magnification produced is - 1/2 . where should the object be placed to get a magnification of -1/5
using mirror formula. prove that in a plane mirror
i)object distance=image distance
ii)image is of same size and it is virtual & erect.
The magnification produced by a plane mirror is +1. What does this
a convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the lens if the image size is equal to the object size. Also find the power of the lens
The refractive indices of water and glass with respect to air are 4/3 and 3/2 respectively. If the speed of light in glass is 2x 108ms-1, find the speed of light in
what r the properties of convex and concave mirror???
Define power of lens.In what SI unit is power of lenses rated?A convex lens has a focal length of 50cm.calculate its power.
find the position of an object when placed in front of a concave mirror of focal length 20 cm produces a virtual image,which is twice size of object.
The magnification produced by a mirror is 1/3 then the type of mirror is --------------. Explain why?
why danger signals are made of red colours
A STUDENT OBTAINS A BLURRED IMAGE OF AN OBJECT ON A SCREEN BY USING CONCAVE MIRROR. IN ORDER TO OBTAIN A SHARP IMAGE ON THE SCREEN, WHERE HE WILL HAVE TO SHIFT THE MIRROR?
5 cm in length is held 25 cm away from a converging lens of focal
length 10 cm. Draw the ray diagram and find the position, size and
the nature of the image formed.
A glass prism is able to produce a spectrum when white light passes through it but a glass slab does not produce any spectrum. Explain why is it so.
When an object is placed 20cm from a concave mirror , a real image magnified three times is formed. Find:
(a) focal length of the mirror.
(b) where must the object be placed to give a virtual image three times the height of the object?
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