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REY [17]
3 years ago
6

Compute the dot product of the vectors u and v​, and find the angle between the vectors. Bold v equals 7 Bold i minus Bold j and

Bold w equals negative Bold i plus 7 Bold j Bold v times Bold w ​= negative 14 ​(Simplify your​ answer.) Find the magnitude of the vectors. StartAbsoluteValue Bold v EndAbsoluteValueequals StartRoot 50 EndRoot and StartAbsoluteValue Bold w EndAbsoluteValueequals StartRoot 50 EndRoot ​(Type exact​ answers, using radicals as​ needed.) The angle between the vectors is nothingdegrees. ​(Type your answer in degrees. Do not round until the final answer. Then round to the nearest tenth as​ needed.)
Physics
1 answer:
OLga [1]3 years ago
3 0

Answer:

\theta = 106.3 degree

Explanation:

As we know that

\vec w = -\hat i + 7\hat j

\vec v = 7\hat i - \hat j

also we know that

\vec v. \vec w = -14

it is given as

\vec v. \vec w = (-\hat i + 7\hat j).(7\hat i - \hat j)

\vec v. \vec w = - 7 - 7 = -14

also we can find the magnitude of two vectors as

|v| = \sqrt{(-1)^2 + (7)^2}

|v| = \sqrt{50}

similarly we have

|w| = \sqrt{(7^2) + (-1)^2}

|w| = \sqrt{50}

now we know the formula of dot product as

\vec v. \vec w = |v||w| cos\theta

-14 = (\sqrt{50})^2cos\theta

\theta = cos^{-1}(\frac{-14}{50})

\theta = 106.3 degree

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<u>Explanation:</u>

Length of silicon bar, l = 10 μm = 0.001 cm

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μn = 1200 cm^2 / V s

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The total current flowing in the bar is the sum of the drift current due to the hole and the electrons.

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A is the area of bar, A = 20 μm = 0.002 cm

I = 1.01 \times 10^-9 \times 0.002 = 2.02 \times 10^-12

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