Examples: Volume of a Cone Video Lecture - Class 9

hello friends this video on surface area
and volume sparked nineteen is brought
to you by exam fear calm no more fear
from example now I will understand the
volume of right so we have already
defined cone as a three-dimensional
shield that tapers smoothly from a flat
piece flat piece from the paper smoothly
to the axis they didn't find this code
base deeper epochs for vortex Hey for my
example on the base of circular and that
base is actually perpendicular to the
axis okay
if you want you can also define fluid as
all the line segment joining the effects
and any point in this circumference of
the cone take all the wines and if you
just draw from this point we need point
to the circumference will actually get
okay so we really cannot dig deep you
take an active you take an own headless
cylinder of Seabees and see my see if
this height is H like this the cone also
has the same mind if you see the radius
is R this also and see if it is so the
cone and the cylinder has same height
and see if it is please pay attention
little critical here would take a cone
take a cylinder you can do this near
home which has same height and same
piece which has same base and seem so
you should see where it is and see my
okay now what you do is you take three
such moves like putting three such bone
which has same radius little bit it has
already equalities high-tension all
three will have I did you see the
heights are maximum now you fill this
cone with water it take the first hole
fill it you see that
what a little advice take the second
cone and fill the game the slender right
you see the water right take the third
cone and again empty the water in this
you see that after three cones
the cylinder is completely filled Hey
so what we notice is three into volume
of cone is nothing but what so notice
that three into volume of cone is equal
to volume of cylinder and the cylinder
has radius R and H cone also has ladies
would have seen values of it is an inch
okay so with that I can see that and
what you sleep is what PI X where G so 3
into volume of 1 is 1 by X square H so
volume of cone is nothing but 1 by 3 Oh
see with this experiment we have seen
that you have taken 3 volume three cones
and three cones of radius R and H it is
alright H was used to film a cylinder of
radius R a clean volume of one one thing
but modulator of it is not energy so
almost inner of units of our energy is
PI R square H
create volume upon this is PI R square H
so for a component 1 by 3 PI R square H
X take some numerical
the hydrate the slant height of the cone
argument so highest rating is very
straight so 5 is 21 and slant-eyed
history
Mota's activity even need to find the
volume alone so we know that volume of
hole is what we are so 1 by 3 PI R
square H so we have our veto we have h 0
2 pi we know that l squared is equal to
R square plus n square L is what's
1928-29 square minus H square that is
straight L square by H square H you
solve it to get seven five six pretty
easy question here the slant-eyed I was
given the radius was not given before
the radius first once we have three DS
in height we can either find the volume
of cone has gone by 3 PI R square H
Monica has a piece of canvas whose media
is given C uses it to have a conical
head made with the base radius assuming
the all-city
Margit in the waist is incurred by the
cutting is approximately 1 in 2 square
we have to find the volume of the thing
that can be made to this so if you see
the height is not needed so first we
have to find the height of the thing and
that can be determined by the fact that
the data is given for the
Camus see the canvas area is PI 21 meter
square wasting this 1 meter square
a so that means that 10 surface area is
Hamish 551 with a square the calories in
young minus V station that is 550 meter
square is the surface video of them
thank thank so you can see that surface
area is given as 5 meters and that is
nothing but PI R so we'll put the values
n that is same so with that if you saw
you get LS 25 so slant height is 25 and
that meaning is defined edge H is
nothing but mu naught L square minus H
so H is nothing but 2 L square minus R
square by u square minus 7 square and
that is nothing but 24 it is meter so we
record another of H once we got the
matter which end value R so we can
easily find the volume of 10 to the
power 1 by 3 PI R square H 3 to 7 hours
24 square and H is 7 7 square and H is
action 24 24 to put the values you get 1
2 3 - that is the good easy service if
you have the tent I mean it was given
common
what is the way stage with that regard
surfaced of the 10 so it's a visiting of
the tenth it is already given me form of
the slant height of the tight-ass land
lighten up then we from height of the
ten once we got the fright of the ten
degrees to fight the quality this is
already given it's pretty easy question
the height of the cone is given 15
centimeter all the volume is given B to
find the radius easy volume is nothing
but 1 by 3 PI R square H so or volume is
1 5 7 is you know I use 2007 you don't
know you saw as you get out as tens and
anyway the use equation a conical pit
fitness in you dig this on land a little
bit conical bit of top 10 meter 3 point
5 meter and this this is 3 point 5 by 2
yes and 12 meter D this is 10 this is a
print of this time eater if you see here
this the depth is also okay how much the
capacity in communities we will just
find the volume of this particular cone
so volume is 1 by 3 PI R square H by 7
is 5 by 2 square which is 12 so you put
the values you get 35 point 8 meter -
okay this is the middle you have to find
that and we know that 1 meter cube is
equal to
it does convert this into heat
okay all right
trying to ABC website five twelve and
thirteen is all about the side 12
centimeter so we have to find the volume
of the solids so we have seen it on
experiment that if you doing a right
triangle it will evolve it you get a
shoe so you get a cone and this say that
it is reward have oversight twelve
centimeters this is 12 this is 12 can we
guess which is cutting in which is 5
obviously the longest side is the
hypotenuse this is 13 and this is 5 so
once we have this data once we
understand that sentence at a ball
around 12 centimeter this will be 5 in
this will be 13 so that means we got a
cone of radius 5 and height is 2 and
with that we can easily find the volume
of the cone so volume of cone is 1 1 by
3 PI R square H is 3 PI R square H is to
put the balloons you get almost 3 1 4
centimeters so in this question that I
come back over that you understand that
if you take a right triangle every
duvall you get first thing second thing
is that you are revolving around well
centimeter side then the height will be
12 and the highest side the longest side
will always be happening the other side
is the base and the base becomes radius
of the cone I heal offbeat is in the
form of a cone he repeated a forms he
that is almost in there to home with a
diameter of 10 point
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