The current, I in an a. c circuit is given by the equation: I = 30sin100πt, where t is the time
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Dec 3, 2024
The current, I in an a. c circuit is given by the equation: I = 30sin100πt, where t is the time in seconds.
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the
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current the current I in an AC circuit
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is given by the
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equation I = 30 sin 1005
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T where
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T is in seconds reduce the
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following from this
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equation number one frequency of the
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current pi value of the current and the
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root me squ of the current to find the
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frequency of the current the first thing
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we need to do is to uh deduct is to
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deduct our
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data and to do that we will now say that
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since we have this
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equation
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I is equal
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to 30
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s
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100
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100
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5 we now equate it with I
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not is equals
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to or will not say sorry I isal to
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i s
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2 5 f
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t so this is what we have we are now
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equating I
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=
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30 as I = I sin 2
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F
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this
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party corresponds with I
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not and if we do that you to find the
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frequency we will now say that this
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uh
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1005 this
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10050 corresponds with
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[Music]
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2 25
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F corresponds with 25 F
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so5 Cor responds with 25
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ft 30 corresponds with I so
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now to solve question one we now say
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that the frequency is equal to
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100 5
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T is equal
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to now we have 25 ft we now write
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25 ft
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Pi will cancel
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Pi T will cancel T and we be left
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with will be left with
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100 is equals
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to this is 100 is equals to we have two
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here 2
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F and dividing both sides by two we now
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have
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this will cancel this 2 into 2 1 2 into
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100 is 50 therefore our frequency f is
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equal to
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50
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HZ let's go to equation two question two
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sorry find the F
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value find the P value of the current to
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find the P value of the current we will
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now say that
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I
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here I not here is the P value I
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corresponds to 30 therefore I which is
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the P value is equal to
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30 therefore we
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now use the unit of I I not which is in
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amp therefore 30
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amp the third question find the square
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of the
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current three to find the root me square
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of the current the first thing we need
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to do is to remember that
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i²
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isal I which is the F current all over <
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tk2 and this is going to give us I note
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here is 30 therefore we have 30 over <
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tk2
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now if we use sord form we now have
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30 < tk2 * <
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tk2 over < tk2 the reason why I said 22
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remember
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that 1 / 1 is = 1 2 / 1 = 2 and 2 / 2 =
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1
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therefore if I sayun
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2k2 is also the same thing as 1 and if I
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now say x * <
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tk2
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over <
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tk2 is the same thing as x
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* one and this is the same thing as X
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therefore we are now applying this same
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method here this is the same thing as
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now if we multiply here we now going to
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have
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30 < tk2 30 byun2 and < tk2 byun2 will
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give
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us <
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TK4 and this is the same thing as 30 <
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tk2 all over sare root of 4 is going to
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give us 2 and 2 into 2 1 2 into 30 will
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give give us 15 and this is going to
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be
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15 <
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tk2 therefore we have our iot me
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squ
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IUN mean
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squ is equal to 15 < tk2
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aamp remember that anair is the unit of
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current but in this case we can now
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still said okay what is RO
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true if we change it into we can now
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still write it as I square is equal to
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21
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point is equal to
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21.
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21 ere ere there and this is the
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final answer
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