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3 years ago

Find the vector v with the given magnitude and the same direction as u. Magnitude ||v|| = 10 Direction u = ⟨-3. 4⟩.

Physics

1 answer:

Alisiya [41]3 years ago

4 0

Answer:

(-6,8)

Explanation:

Since v has direction as u, it must be a multiple n of u.

$\sqrt{(-3n)^+(4n)^2}=10\\9n^2+16N^2 =100\\n^2=4\\n=2$

therefore v = (3×2, 4×2) = (-6,8)

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andreyandreev [35.5K]

Answer:

v = -6m/s

Explanation:

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For t = 1:

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4 years ago

A mechanic pushes a 2.60 ✕ 103-kg car from rest to a speed of v, doing 5,430 J of work in the process. During this time, the car

Oduvanchick [21]

Part A. We are given that a car is pushed from rest to a final speed doing 5430 Joules of work. -

To determine the final velocity we will use the work and energy theorem which states that the work done is equal to the change in kinetic energy:

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Since the car starts from rest this means that the initial kinetic energy is zero:

$W=K_f$

The kinetic energy is given by:

$K=\frac{1}{2}mv^2$

Substituting in the formula we get:

$W=\frac{1}{2}mv_f^2$

Now, we solve for the final velocity. First, we multiply both sides by 2 and divide both sides by the mass:

$\frac{2W}{m}=v_f^2$

Now, we take the square root to both sides:

$\sqrt{\frac{2W}{m}}=v_f$

Now, we plug in the values:

$\sqrt{\frac{2(5430J)}{2.6\times10^3kg}}=v_f$

Solving the operations:

$2.04\frac{m}{s}=v_f$

Therefore, the final velocity is 2.04 m/s.

Part B. Now, we use the following formula for work:

$W=Fd$

Where "F" is the force and "d" is the distance.

Now, we set this equation equal to the work done by the force:

$Fd=5430J$

Now, we divide both sides by the distance "d":

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2 years ago

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Nitella [24]

Answer:

160 m

Explanation:

distance covered in 1 s = 8 m

therefore, distance covered in 20 s = 8 * 20 m = 160 m

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3 years ago

The ceiling of a large symphony hall is covered with acoustic tiles which have small holes that are 4.35 mm center to center. If

zvonat [6]

Answer:

The distance between their eye and the ceiling is 33.06 m.

Explanation:

Given that,

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Wavelength, $\lambda=550\ nm$

We need to find the distance between their eye and the ceiling. Using Rayleigh criteria, we get the distance as follows :

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vampirchik [111]

Answer:

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3 years ago