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3 years ago

You take a 3 hour nap on a train traveling 40 miles per hour

Physics

2 answers:

Ganezh [65]3 years ago

7 0

120 miles - 3 x 40 = 120

Svetradugi [14.3K]3 years ago

5 0

Answer:

120 miles

Explanation:

Speed = distance traveled/ time taken.

Distance traveled = speed * time taken

Speed = 40 miles per hour, time = 3 hours.

Distance = 40*3

The train's traveled distance is 120 miles.

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Answer:

1. $E(r) = \frac{\alpha}{4\pi \epsilon_0}(2 - \frac{r}{R})$

2. $E(r) = \frac{1}{4\pi \epsilon_0}\frac{\alpha R}{r}$

3.The results from part 1 and 2 agree when r = R.

Explanation:

The volume charge density is given as

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2. For r> R, the total charge of the enclosed cylinder is equal to the total charge of the cylinder. So,

$Q_{enc} = \int\limits^R_0 {\rho(r)h} \, dr = \alpha \int\limits^R_0 {(1-r/R)h} \, dr = \alpha h(r - \frac{r^2}{2R})\left \{ {{r=R} \atop {r=0}} \right. = \alpha h(R - \frac{R^2}{2R}) = \alpha h\frac{R}{2} \\E2\pi rh = \frac{\alpha Rh}{2\epsilon_0}\\E(r) = \frac{1}{4\pi \epsilon_0}\frac{\alpha R}{r}$

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