Hello. Can anyone help me with this 2 questions. I need to submit it tonight. Please provide the answer with the working.Don't answer it if you don't know! Thanks.
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Step-by-step explanation:
you know that you can change and reform any equation by doing the same operation to everything on the left and on the right side of the "=" sign ?
that way you can change the appearance of terms and the locations of variables or constants without changing the expressed balance.
this is like in a 2-bowl scale, where you can add or remove the same weight on both sides to keep the scale in balance.
and that is the principle, when we transform equations.
4.
V = RI
we want to have "I" alone on one side. so, what do we need to do ? a division by "R", of course.
again, it has to happen on both sides of the "scale" ...
V/R = I
I = 50/2.5 = 20 A (or amps)
5.
the area of a circle is
A = pi × r²
with r being the radius.
now, r should stand alone (and is the result of the other values). so, what do we need to do ?
well, first we divide both sides by pi :
A/pi = r²
and now ? how do we get r from r² ? we pull the square root (sqrt()) ! again, as always, both sides :
r = sqrt(A/pi)
r = sqrt(100/pi) = sqrt(31.83098862...) =
= 5.641895835... ≈ 5.64 mm
Answer:
Ohm's Law
[tex]V=RI[/tex]
where:
Part (a)
Given equation:
[tex]\implies V=RI[/tex]
Divide both sides by R:
[tex]\implies \dfrac{V}{R}=\dfrac{RI}{R}[/tex]
Cancel the common factor:
[tex]\implies \dfrac{V}{R}=\dfrac{ \diagup\!\!\!\!\!R\:I}{\diagup\!\!\!\!\!R}[/tex]
Therefore:
[tex]\implies I=\dfrac{V}{R}[/tex]
Part (b)
Given:
Substitute the given values into the formula and solve for I:
[tex]\implies I=\dfrac{V}{R}[/tex]
[tex]\implies I=\dfrac{50}{2.5}[/tex]
[tex]\implies I=20\:\:\sf A[/tex]
[tex]\textsf{Area of a circle}=\pi r^2 \quad \textsf{(where r is the radius)}[/tex]
Part (a)
Given formula:
[tex]\implies A=\pi r^2[/tex]
Divide both sides by [tex]\pi[/tex]:
[tex]\implies \dfrac{A}{\pi}=\dfrac{\pi r^2}{\pi}[/tex]
Cancel the common factor:
[tex]\implies \dfrac{A}{\pi}=\dfrac{\diagup\!\!\!\!\!\pi r^2}{\diagup\!\!\!\!\!\pi}[/tex]
[tex]\implies r^2=\dfrac{A}{\pi}[/tex]
Square root both sides:
[tex]\implies \sqrt{r^2}=\sqrt{\dfrac{A}{\pi}}[/tex]
[tex]\implies r=\sqrt{\dfrac{A}{\pi}}[/tex]
Part (b)
Given:
Substitute the given value into the formula and solve for r:
[tex]\implies r=\sqrt{\dfrac{A}{\pi}}[/tex]
[tex]\implies r=\sqrt{\dfrac{100}{\pi}}[/tex]
[tex]\implies r=5.64\:\:\sf mm \:(2 \:dp)[/tex]