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Mars2501 [29]
2 years ago
7

Solve the following quadratic equations:2x² - 4x - 9 = 0 x₊ = 1 + √22/2Answersx_ = 1 - √22/2

Physics
1 answer:
Pavel [41]2 years ago
6 0

The root quadratic equation of 2x^{2}  - 4x - 9 = 0 is x=\frac{2+\sqrt{22}}{2},\:x=\frac{2-\sqrt{22}}{2}

What is the formula used to calculate the quadratic equation?

To solve the quadratic equation use the formula of x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}

Find the quadratic equation by using the formula ?

On comparing with 2x^{2}  - 4x - 9 = 0

We get , a=2 , b=-4 , c=-9

D=b^{2} +7\\\\\\=(-4)^{2} +7*2*(-9)\\\\=-16-126\\\\=110

By using the formula,

For a quadratic equation of the formax^2+bx+c=0 the solutions are

x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}

X==\frac{-\left(-4\right)\pm \sqrt{\left(-4\right)^2-4\c* \:2\left(-9\right)}}{2\c* \:2}\\\\\sqrt{\left(-4\right)^2-4\cdot \:2\left(-9\right)}\\\\

Apply rule,

-(-a)=a\\\\=\sqrt{\left(-4\right)^2+4\cdot \:2\cdot \:9}\\\\

Apply exponent rule,

(-a)^{n} =a^{n} if n is even

(-4)^{2} =4^{2}

\sqrt{4^2+4\cdot \:2\cdot \:9}

Multiply the numbers :

4*2*9=72\\\\\sqrt{4^2+4\cdot \:2\cdot \:9}\\\\4^{2} =16\\\\=\sqrt{16+72}\\\\

Add the number  =\sqrt{88}

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Ivanshal [37]

Answer:

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Explanation:

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6 0
3 years ago
What is the displacement current in the capacitor if the potential difference across the capacitor is increasing at 500
padilas [110]

Answer:

I = 1.21x10^-5 A

Explanation:

You are missing the first part of the problem. This is an example, but it will give you the idea of how to solve yours with your data.

The first part is like this:

<em>A      4.0 cm  diameter parallel plate capacitor has a  0.44 m  m    gap. What is the displacement current in the capacitor if the potential difference across the capacitor is increasing at 500,000 V/s?</em>

Now with this, we can solve the problem.

In order to do this, we need to use the following expression:

q = CV (1)

Where:

C: Capacitance of a parellel capacitor (in Faraday)

q: charge of plate or capacitor (In coulombs)

V: voltage in Volts.

However, we need is the current, and we have data of potential difference, so, all we have to do is divide the expression between time so:

q/t = CV/t

And the current is q/t, thus:

I = C * V/t (2)

And finally, Capacitance C with two plates of area A separated by a distance d is:

C = Eo*A/d (3)

Where:

Eo = constant equals to 8.85x10^-12 F/m.

A = Area of the plate, in this case, πr²

d = gap of the capacitor.

Let's calculate first the Capacitance using equation (3):

C = 8.85x10^-12 * π * (0.04/2)² / 0.00046 = 2.42x10^-11 F

Now, it's time to use equation (2) and solve for I:

I = 2.42x10^-11 * 500,000

I = 1.21x10^-5 A

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3 years ago
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olasank [31]
Hello.

The solor system is organized by the smallest star to the largest and by the 8 planets. it is also organized by how much gas a planet has. But it is also orgainzed becasue of gravity.

The different divisions are <span>planets, moons, asteroids, comets and meteoroids.
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Have a nice day

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3 years ago
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zhuklara [117]

Answer:

#See solution for details.

Explanation:

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