The specific gravity of mantle rock is about 3.3. truefalse

You apply a potential difference of 5.70 v between the ends of a wire that is 2.90 m in length and 0.654 mm in radius. the resul

photoshop1234 [79]

1) First of all, let's find the resistance of the wire by using Ohm's law:
$V=IR$
where V is the potential difference applied on the wire, I the current and R the resistance. For the resistor in the problem we have:
$R= \frac{V}{I}= \frac{5.70 V}{17.6 A}=0.32 \Omega$

2) Now that we have the value of the resistance, we can find the resistivity of the wire $\rho$ by using the following relationship:
$\rho = \frac{RA}{L}$
Where A is the cross-sectional area of the wire and L its length.
We already have its length $L=2.90 m$ , while we need to calculate the area A starting from the radius:
$A=\pi r^2 = \pi (0.654\cdot 10^{-3}m)^2=1.34 \cdot 10^{-6}m^2$

And now we can find the resistivity:
$\rho = \frac{RA}{L}= \frac{(0.32 \Omega)(1.34 \cdot 10^{-6}m^2)}{2.90m}= 1.48 \cdot 10^{-7}\Omega \cdot m$

7 0

4 years ago

a furnace supplies 28kW of thermal power at 300C to an engine and exhausts waste energy at 20C. At the very best, how much work

DochEvi [55]

Answer:

The amount of work we could expect to get out of the system per second = 28,000J/s

Explanation:

Given the power supplied to the system as 28kW;

Energy = power / time

At very best, the amount of work we could expect to get out of the system per second = 28,000 W / 1 second = 28,000J/s

Therefore, for a a furnace which supplies 28kW of thermal power at 300C to an engine and exhausts waste energy at 20C.

At the very best, the amount of work we could expect to get out of the system per second = 28,000J/s

6 0

3 years ago

Some scientists speculate that our universe is not the only universe that exists, but the only one we can gather evidence about.

o-na [289]

This idea is called the multiverse theory

<h3>What is the Multiverse theory?</h3>

According to multiverse hypothesis, our universe, which spans tens of billions of light-years and contains hundreds of billions of galaxies and almost innumerable stars, may not be the only one. Instead, there may be a whole distinct world, far away from ours, and then another, and another. In fact, there may be an infinite number of universes, each with its own set of physical laws, stars and galaxies (if they can exist in those worlds), and perhaps even sentient civilizations.

The idea of the multiverse appears in a few branches of physics (and philosophy), but inflation theory provides the best-known example. According to inflation theory, a hypothetical occurrence took place when our universe was really young—less than a second old. According to NASA, the cosmos had a brief period of fast expansion before "inflating" to become several orders of magnitude larger than it had been.

According to Heling Deng, a cosmologist at Arizona State University and an authority on the multiverse hypothesis, the expansion of our universe is assumed to have stopped some 14 billion years ago. However, Deng noted in an email to Live Science, "inflation does not disappear everywhere at the same time." It's possible that if inflation slows down in one area, it picks up in another.

to learn more about the multiverse theory go to - brainly.com/question/12210965

#SPJ4

6 0

1 year ago

Which two types of information are found in an elements box in the periodic table

Pani-rosa [81]

Answer:

Each box represents an element and contains its atomic number, symbol, average atomic mass, and (sometimes) name.

Explanation:

4 0

3 years ago

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