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3 years ago

If 170 degrees F air feels warm and comfortable to us, why does swimming in 70 degree F water feel cold ?

1 answer:

3 0

Your body loses heat to the water faster than it loses heat to the air. Water has a higher heat capacity, so it is better at extracting heat than air is.

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A pathogen has entered your body and you become sick. You develop a fever and vomit. This is your body's way of trying to mainta

larisa [96]

Homeostasis is the answer

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3 years ago

An automobile engineer is revising a design for a conical chamber that was originally specified to be 12 inches long with a circ

Sidana [21]

The volume of the cylinder is:
V= pi* (r^2) * h.

So the volume is = pi * (5.7/2)^2 * 12 = 306.2 in^2.
Since it is scaled up by the factor of 1.5, so we have to multiply each dimension with 1.5.
That means the diameter will be 8.55 and the height will be 18. so the scaled up volume will be

=pi * ((5.7*1.5)/2)^2 * (12*1.5)

The answer then would have to be 1033.5

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4 years ago

A ceiling fan draws a current of 0.625 A and has a voltage of 120 V. The resistance of the ceiling fan, to the nearest whole num

Fiesta28 [93]

So we want to know what is the resistance of the ceiling fan if the current I=0.625 A and the voltage V=120 V. So we can get the resistance from Ohms law: I=V/R where I is the current, V is voltage and R is resistance. So the resistance is R=V/I. Now we input the numbers and get: R=120/0.625=192 Ω. That is resistance to the closest whole number.

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3 years ago

Read 2 more answers

Use the drop-down menus to answer each question about hurricanes. What helps create the spin in a hurricane? What is the center

Leto [7]

1.coriolis effect!

2. eye of the storm!

3. warm ocean water!

these should be correct!

6 0

2 years ago

g initial angular velocity of 39.1 rad/s. It starts to slow down uniformly and comes to rest, making 76.8 revolutions during the

MrRa [10]

Answer:

Approximately $-1.58\; \rm rad \cdot s^{-2}$ .

Explanation:

This question suggests that the rotation of this object slows down "uniformly". Therefore, the angular acceleration of this object should be constant and smaller than zero.

This question does not provide any information about the time required for the rotation of this object to come to a stop. In linear motions with a constant acceleration, there's an SUVAT equation that does not involve time:

$v^2 - u^2 = 2\, a\, x$ ,

where

$v$ is the final velocity of the moving object,
$u$ is the initial velocity of the moving object,
$a$ is the (linear) acceleration of the moving object, and
$x$ is the (linear) displacement of the object while its velocity changed from $u$ to $v$ .

The angular analogue of that equation will be:

$(\omega(\text{final}))^2 - (\omega(\text{initial}))^2 = 2\, \alpha\, \theta$ , where

$\omega(\text{final})$ and $\omega(\text{initial})$ are the initial and final angular velocity of the rotating object,
$\alpha$ is the angular acceleration of the moving object, and
$\theta$ is the angular displacement of the object while its angular velocity changed from $\omega(\text{initial})$ to $\omega(\text{final})$ .

For this object:

$\omega(\text{final}) = 0\; \rm rad\cdot s^{-1}$ , whereas
$\omega(\text{initial}) = 39.1\; \rm rad\cdot s^{-1}$ .

The question is asking for an angular acceleration with the unit $\rm rad \cdot s^{-1}$ . However, the angular displacement from the question is described with the number of revolutions. Convert that to radians:

$\begin{aligned}\theta &= 76.8\; \rm \text{revolution} \\ &= 76.8\;\text{revolution} \times 2\pi\; \rm rad \cdot \text{revolution}^{-1} \\ &= 153.6\pi\; \rm rad\end{aligned}$ .

Rearrange the equation $(\omega(\text{final}))^2 - (\omega(\text{initial}))^2 = 2\, \alpha\, \theta$ and solve for $\alpha$ :

$\begin{aligned}\alpha &= \frac{(\omega(\text{final}))^2 - (\omega(\text{initial}))^2}{2\, \theta} \\ &= \frac{-\left(39.1\; \rm rad \cdot s^{-1}\right)^2}{2\times 153.6\pi\; \rm rad} \approx -1.58\; \rm rad \cdot s^{-1}\end{aligned}$ .

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3 years ago