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Fittoniya [83]
3 years ago
15

Car B starts at point X and moves clockwise around a circular track at a constant rate of 2 mph. Ten hours later, Car A leaves f

rom point X and travels counter-clockwise around the same circular track at a constant rate of 3 mph. If the radius of the track is 10 miles, for how many hours will Car B have been traveling when the cars have passed each other for the first time and put another 12 miles between them (measured around the curve of the track)?
Physics
1 answer:
stealth61 [152]3 years ago
4 0

Answer:

20.96 h

Explanation:

The perimeter of the track is 2*pi*r = 20pi miles

In 10 hours, car B would have moved 20miles. So, when Car A leaves from point X, car B is 20pi - 20 miles from point X counter-clockwise and car A.

From here, we can express the distance of A from X like this:

xa = 3t

And the distance of B would be:

xb = 20pi - 20 - 2t

The time t where they would passed each other and put  12 miles between them would be the one where xa - xb is equal to 12:

xa - xb = 12

3t - (20pi - 20 - 2t) = 12

5t = 20 pi - 8

t = (20pi - 8)/5 = 10.96 h

Remember to add this value to the 10 hours car B had already been racing:

t = 20.96h

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Answer:

the answer is a)5.82s

Explanation:

Hello!

The first thing we must understand to solve this exercise is that a capacitor has the following characteristic function

V=(Vo)e^{-t/RC}

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we must consider that the final voltage is half of the initial voltage so we deduce the following equation

V=Vo/2

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\frac{Vo}{2} =(Vo)e^{-t/RC}\\0.5=e^{-t/RC}\\ln(0.5)=ln(e^{-t/RC})\\ln(0.5)=\frac{-t}{RC} \\t=-(RC)ln0.5

finally with the equation ready, we use the resistance and capacitance values ​​to find the time value

t=-(4000)(0.0021)ln(0.5)=5.82s

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Heat will flow from the water into the air by convection .
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Earth’s surface is subjected to unusually high rates of weathering. The Moon and some of the inner planets of our solar system a
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<h2>Answer:</h2>

<em><u>Running water on the Surface of Earth.</u></em>

<h2>Explanation:</h2>

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For Netwon's second law, the force is also equal to the proton mass times its acceleration:
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So we have
ma=qvB
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4 0
3 years ago
Question C) needs to be answered, please help (physics)
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(a) Differentiate the position vector to get the velocity vector:

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<em></em>

(b) The velocity at <em>t</em> = 2.00 s is

<em>v</em> (2.00 s) = (3.00 m/s) <em>i</em> - (16.0 m/s) <em>j</em>

<em></em>

(c) Compute the electron's position at <em>t</em> = 2.00 s:

<em>r</em> (2.00 s) = (6.00 m) <em>i</em> - (16.0 m) <em>j</em> + (2.00 m) <em>k</em>

The electron's distance from the origin at <em>t</em> = 2.00 is the magnitude of this vector:

||<em>r</em> (2.00 s)|| = √((6.00 m)² + (-16.0 m)² + (2.00 m)²) = 2 √74 m ≈ 17.2 m

(d) In the <em>x</em>-<em>y</em> plane, the velocity vector at <em>t</em> = 2.00 s makes an angle <em>θ</em> with the positive <em>x</em>-axis such that

tan(<em>θ</em>) = (-16.0 m/s) / (3.00 m/s)   ==>   <em>θ</em> ≈ -79.4º

or an angle of about 360º + <em>θ</em> ≈ 281º in the counter-clockwise direction.

3 0
3 years ago
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