Comparing Lengths of Line Segments Video Lecture | Mathematics for Class 6

hello friends this video on
understanding elementary shapes part
three is got to you by example calm no
more your calm exam now ruler is not the
only way to measure or compare lengths
there is any different we used to
compare them let us look at some common
themes the first common read would be
observation see even without a word
without any other thing just by looking
at the line segment you can say which is
longer and which is shorter for example
if you have these two line segments so
even if I do not give a ruler you can
very clearly see that this one is longer
so that's quite evident so just by
observation we could say this but there
is a problem with observation can you
tell me what now here in this is in this
example the two lines the annex there is
a huge difference between their lengths
so just by looking at it we could easily
say which is shorter and which is longer
but if you have two line segments which
are comparable in length like these do
now now if I ask you to just observe and
tell which is longer it might be little
challenging because just by looking at
it you might not be able to decide which
one is longer so in this kind of
scenario you might need to you know take
the second approach and the second
circuit approach is to use a ruler like
what we did in the previous length so
how does the Google help
so here even if you have two compatible
line segments using the ruler you can
precisely look at it length so for
example here that length is
approximately 10 centimeters in the
second is the length is slightly more
than 11 centimeters so but with this
measurement you can say that the length
of this line segment is more than the
first one so this is perfectly fine so
the ruler seems to be more accurate
total size and more convenient to use as
well my talent and issue involves with
ruler as well and that's if it doesn't
cause the positioning error
what does this position get it now
whenever we make measurements using a
ruler we need to ensure that our eyes is
pleased exactly vertically above demand
for which we are doing the observation
that is this so to get a correct measure
the I must be pleased just vertically
above the one let's look at this picture
let's say that this is an object which
need to each leg needs to be measured
and this is your do list so if you are
measuring the length of this object so
if you are taking the reading at this
point your eyes should be placed exactly
vertically above this point you should
not look at it from an angry disposition
because the moment you look at it from
this position you do not have to see
this point instead you read it somewhere
here so let me when you look at it from
here you read it somewhere here so you
end up reading in accurate value so
therefore to avoid errors happening due
to anterior giving it is very important
that the iron must be positioned exactly
vertically above demand where you are
taking a reading so this is one this is
one problem that could arise while
taking readings with a ruler however if
it can be avoided if you place your
re-racking above the mark but do you
think there is any other option of using
something else other than the rule is
[Music]
yes then you can even have a lens using
a divider I am showing that seen a
divider in your geometry box this is how
it looks it has two pointed ends like
this and you can
then these two arms of the divider are
flexible so you can open them you can
close them so you open them so when you
open them it gets widen when you close
them it gets narrow so let's say that
these are the three line segments we
need to use the things the green and the
blue one now you have to compare their
lengths now it's just using a ruler what
you do is you adjust the opening of the
divider in such a way that the two ends
of the divider at the two end points of
the line segment mean that way you
basically get the length of the line
segment in the opening of the divider
now retain the same opening of the
dividers a lot of order it take the same
divider between the same opening and
pleasement
on the second line segment and what do
you see you see that the second line
segment is slightly more than the
opening of the divider which shows that
the length of the second line segment is
more because in this is the divider is
the opening of the divider is smaller
now if you please stay in revival in the
third line segment you can see that the
opening of the dividers which cover
almost half of the line segment so
remaining half it would not cover them
the blue line segment is even longer
than the green one so in this fashion
using the dividers also you can
calculate length of multiple line
segment and in this case the transfers
of positioning error is less that's
because here you are not reading any
value effect so you just need to make
make sure that the two ends of the
dividers
overlap with the two ends of the line
segment and that's how you can get an
idea about the length of that line
segment now you might ask that okay if I
am using divider even though I get an
idea about which line segment is longer
and which one is shorter
what if I want to know the exact length
of the line segment for example in this
case we got to note that the blue one
the longest and the pink one is the
shortest but if I want to know the exact
length of the pink line thing then what
do I do
so in fact what you need to do is first
you take the length of the line segment
if the opening of the divider which you
have already done like you place the two
ends of the divider on the two ends of
the line segments that means the opening
of your divisor now tells you the length
of the line segment
now you take a ruler please with and
please the divisor above that ruler in
structuring that one end of the divisor
coincides with the zero of the scale
that is the coincides with the beginning
starting point of the scale and then to
observe the reading carefully and this
is how you can precisely find out the
exact length so using the divider you
set the opening of the dividers in
accordance with the length of the line
segment then place the divider over the
ruler and find out the exact length so
in this way we can make use of a divider
to compare them so you taught three
different options observation ruler and
divider so out of these you would field
as using a divider is a better approach
because the chances of error is less
fuel thank you please visit example.com
for free quality education you can learn
with a simple four-step learning process
wearing you can watch video lessons you
can ask your questions you can grab your
notes and you can take a free online
test we have content for class six to
twelve on physics chemistry mathematics
and biology along with practical videos
so please subscribe to our channel for
daily updates thank you