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3 years ago

Why are dark matter and dark energy described as dark

1 answer:

3 0

Dark matter is called dark because it does not appear to interact with the electromagnetic field, which means it does not absorb, reflect or emit electromagnetic radiation, and is therefore difficult to detect.

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If an electromagnetic wave has components Ey = E0 sin(kx - ωt) and Bz = B0 sin(kx - ωt), in what direction is it traveling?

fomenos

Answer:

Its traveling in the +x direction

Explanation:

The E-field is in the +y-direction, and the B-field is in the +z-direction, so it must be moving along the +x-direction, since the E-field, B-field and the direction of moving are all at right angles to each other.

8 0

3 years ago

The law of conservation of matter states that matter can neither be created nor destroyed. How is the law of conservation of mat

FromTheMoon [43]

<span>The law of conservation of matter and energy relates to the cycles in nature, and by that it is also applied to rocks and other materials. All of the rock in the Earth is recycled and accounted for during the rock cycle. Rocks experience physical change, the composition of the material stays the same, it may just change how it looks and chemical changes occur (the suubstance undergoes a chemical reaction that changes the actual makeup of the substance).</span>

4 0

3 years ago

Which process can transfer energy to a solid metal block

gladu [14]

Eneregy is the ability to to do work it takes work to heat someone heat is energy put the solid metal block in a campfire and heat it up tada wait, we need the options, nevermind

4 0

3 years ago

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A cubical box measuring 1.29 m on each side contains a monatomic ideal gas at a pressure of 2.0 atm How much thermal energy do t

Marrrta [24]

Answer:

a) $U = 652.545\,kJ$ , b) $v \approx 659.568\,\frac{m}{s}$

Explanation:

a) According to the First Law of Thermodinamics, the system is not reporting any work, mass or heat interactions. Besides, let consider that such box is rigid and, therefore, heat contained inside is the consequence of internal energy.

$Q = U$

The internal energy for a monoatomic ideal gas is:

$U = \frac{3}{2} \cdot n \cdot R_{u} \cdot T$

Let assume that cubical box contains just one kilomole of monoatomic gas. Then, the temperature is determined from the Equation of State for Ideal Gases:

$T = \frac{P\cdot V}{n\cdot R_{u}}$

$T = \frac{(202.65\,kPa)\cdot(1.29\,m)^{3}}{(1\,kmole)\cdot(8.314\,\frac{kPa\cdot m^{3}}{kmole\cdot K} )}$

$T = 52.325\,K$

The thermal energy contained by the gas is:

$U = \frac{3}{2}\cdot (1\,kmole)\cdot (8.314\,\frac{kPa\cdot m^{3}}{kmole\cdot K})\cdot (52.325\,K)$

$U = 652.545\,kJ$

b) The physical model for the cat is constructed from Work-Energy Theorem:

$U = \frac{1}{2}\cdot m_{cat} \cdot v^{2}$

The speed of the cat is obtained by isolating the respective variable and the replacement of every known variable by numerical values:

$v = \sqrt{\frac{2 \cdot U}{m_{cat}}}$

$v = \sqrt{\frac{2\cdot (652.545 \times 10^{3}\,J)}{3\,kg} }$

$v \approx 659.568\,\frac{m}{s}$

3 0

3 years ago

7. Which quantity is the transfer of energy?<br> force<br> motion<br> work

Arisa [49]

In this exercise we have to know the definition of energy to understand what is transferred to a body, like this:

Work

<h2>What is energy?</h2>

Despite being used in many different contexts, the scientific use of the word energy has a well-defined and precise meaning: Innate potential to perform work or perform an action. Anything that is working, moving another object, or heating it up, for example, is expending (transferring) energy.

With this definition we can say that the only alternative that responds to this is work.

See more about energy at brainly.com/question/1932868

6 0

2 years ago

Read 2 more answers