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A load of 5N gives an extension of 0.56cm in a wire which obeys Hooke’s law. What is the extension
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Jan 8, 2025
A load of 5N gives an extension of 0.56cm in a wire which obeys Hooke’s law. What is the extension caused by a load of 20N?
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0:01
a loot of 5 Newton gives an extension of
0:05
0.56 cm in a wire
0:10
which obeys hooks
0:12
slow what is the extension caused by a
0:16
load of 20
0:17
Newton now we need to extract our data
0:21
and to do so we need to see that our
0:24
applied
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force f
0:30
is equal to 5 Newton this
0:34
is 5
0:37
Newton it gives an extension of 0.56 cm
0:41
in a
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wi which of these hooks so the
0:47
extension E1 is equals to
0:51
0
0:54
56
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CM now
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what is the extension costed by load of
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20 Newton what is
1:10
E2
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E2 caused by a load this it should
1:18
be fub1
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and
1:25
FS2 at this point they say costed by a
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load of 20 Newton therefore this F2 is
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equal to
1:33
20
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Newton therefore the next thing we need
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to do is to remember that f is equals to
1:42
or F is directly proportional to
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extension which implies that f is equal
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to k e and in this context in this
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question we deal with e equal to e isal
2:06
to E1 and at the same time e is equals
2:12
to
2:14
E2 at the same time we also have F isal
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to fub1
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and FAL
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to
2:26
F2 therefore it is easy to say that
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F1 is equal
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[Music]
2:33
to
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k e one why because if you have F
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directly proportional to e is the same
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thing as F isal to k e and K is the
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first constant therefore when we go back
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now we will see that fub1 isal to K E1
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and F 2 is equal
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to
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K
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E2 hence when we use this
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formula this equation one and this
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equation two therefore
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using equation one
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using
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one we have f is equal to K
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E1 F isal to K E1 and we know
3:38
that so fub1 is equal to K E1 and we
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know that fub1 is equals to what 5 new
3:45
but we need to make K subject of the
3:47
formula because we don't know what K is
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this implies that K isal to fub1
3:56
over
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E1 F1 E1 and
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this is equals to since F1 here is 5
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Newt you write 5 over E1 here is
4:14
0.56 therefore we write
4:18
here
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0.
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56 and remember this is in Newton and
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this is in cm and we are asked to leave
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our answer in newon cm therefore the
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next thing we need to do now is to say 5
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/
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056 when you divide when you use
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calculator and divide this you end up
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having
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8
4:50
8
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93 Newton per
4:56
CM which is K therefore we have the
5:00
value of k k is equal to
5:07
8.93 Newton per
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cm and this is equation
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three we can also say now
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using
5:22
using equation 2 we
5:26
have F2 = to
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K
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E2 and we asked from the question what
5:36
is the extension CA by a load of 20 so
5:40
we are now to find E2 and to find E2 we
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make it subject of the formula which
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implies
5:47
that E2 is equal
5:50
to this is F2 over K F2 over K which is
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going to be
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E2 here is equals to what we don't know
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F2 here is equals to what when you go
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back to our data you will see that F2 is
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20 therefore you write 20
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/ and K here is
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8.93 therefore you divide it by
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8.93 remember that the unit of F2 is in
6:25
Newton and the unit of K is in Newton
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per
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CM so this over
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this and this is going to give us you
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should divide 20 by
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8.93 you're going to
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have
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2 uh using calculator
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2
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24
6:56
cm remember the Newton will cancel
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Newton and and
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1/ 1/ CM is cm isal to 1 * CM 1 which
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isal 1 can 1 which isal CM therefore we
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have our final answer is 2.24 CM you can
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further convert it into C Into Me by
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dividing the whole of this by 100
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2.24 / by
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100 then what you have in
7:34
Meers can now be written in m and this
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is our final answer
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