Magnification of Spherical Mirror - Light Reflection & Refraction, Science, Class 10 Video Lecture

hello friends this video on light
reflection and diffraction pattern level
is brought to you by exam feel calm no
more fear from exam please make sure
that you have watched all the videos Tim
Barton before going ahead with part 11
so now we will talk about magnification
of a spherical mirror so this
magnification is the parameter which
will tell us what would be the size of
the image that means whether the image
will be in enlarged or the image will be
diminished or it will be of the same
size if it is bigger how much bigger it
will be so it is a measure of the size
of the image so it is a measure of how
large or how small an image is with
respect to the object right so how do i
define or how do i express magnification
so magnification is denoted by a small m
and it is defined as the size of the
image by size of the object so H -
denote the size of the image and H
denotes the size of the object now let
us try to look at the magnification in
case of a concave mirror let us suppose
this is a concave mirror now what
happens in case of a concave mirror what
kind of image do we normally get in case
of a concave mirror okay let us try to
find out magnification in case of
concave mirror in a concave mirror your
image would be a dash B dash / a B so
this becomes now in nm in a concave
mirror you always get most of the times
you get real and inverted images that
means your magnification is most of the
times negative because H dash is
negative it is an inverted image so H
dash will be negative so that means it
is a dash B dash divided by a B if a
dash B Dash is the size of the image and
means the size of the object now a - B -
looking at the figure in which we have
plotted in the last slide we saw that a
- B - by ad is equal to P B - divided by
P B right from the property of
similarity of triangles so I am making
use of the same equations so we can
write it as minus PB - divided by PB
what was PB - it was nothing but - B for
a concave method whatever speedy it was
nothing but - loop so this magnification
becomes equal to minus v by u so we can
define magnification in two ways that is
height of the image by height of the
object and we can also write it as image
distance divided by object distance
similarly let us look at magnification
fall upon vex method for a convex mirror
since image form this virtual and erect
so this will be H - by H so that that
means this will remain as a - V - / a B
so this will become TB dash divided by
PB now in case of a convex mirror PB
dash is V but it is plus V and P V is U
with a minus u so in this case also we
get magnification is equal to minus V by
u so we can define magnification as
ratio of the height of the image to the
height of the object or it can be
defined as the ratio of the image
distance to the object distance so this
was all about our discussion on
spherical mirror so what all did we
study we saw the different types of
spherical mirrors how do they form
images how do the location or the nature
of the image changes within object
distance or with the focal length we
talked about the mirror equation and we
also talked about the magnification of
the spherical letters now be thank you
please visit exam fee or comm - watch
free educational videos try free online
tests get the best quality study
materials
study from the best tutors and mentors
and much more thank you once again