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4 years ago

Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space?

Physics

1 answer:

elena-s [515]4 years ago

4 0

The answer is; The cloud is cool and lies between you and a hot star.

Absorption lines occur when the electrons of an atom absorb energy through a specific wavelength of light and the electrons ‘jumps’ from a lower energy level to a higher energy level. Absorption lines are viewed as black lines in a continuous spectrum

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rocks move trough the rock cycle through uplift,folding,and faulting cased by movements of the earth´s________

garik1379 [7]

Tectonic plates and convection cells move tectonic plates

4 0

3 years ago

An ideal gas Carnot cycle with air in a piston cylinder has a high temperature of 1000 K and a heat rejection at 400 K. During t

vivado [14]

Answer:

W / n = - 9133 J / mol, W / n = 3653 J / mol , e = 0.600

Explanation:

The Carnot cycle is described by

$e= 1 - Q_{c} / Q_{H} = 1 - T_{c} / T_{H}$

In this case they indicate that the final volume is

V = 3V₀

In the part of the heat absorption cycle from the source is an isothermal expansion

W = n RT ln (V₀ / V)

W / n = 8.314 1000 ln (1/3)

W / n = - 9133 J / mol

During the part of the isothermal compression in contact with the cold focus, as in a machine the relation of volumes is maintained in this part is compressed three times

W / n = 8.314 400 (3)

W / n = 3653 J / mol

The efficiency of the cycle is

e = 1- 400/1000

e = 0.600

6 0

3 years ago

A sample of n2 gas occupies a volume of 746 ml at stp. What volume would n2 gas occupy at 155 ◦c at a pressure of 368 torr?

musickatia [10]

Answer:

2.41 L

Explanation:

We can solve the problem by using the ideal gas equation, which can be rewritten as:

$\frac{p_1 V_1}{T_1}=\frac{p_2 V_2}{T_2}$

where we have:

$p_1 = 1.01\cdot 10^5 Pa$ (initial pressure is stp pressure)

$V_1 = 746 mL = 0.746 L = 7.46\cdot 10^{-4}m^3$ is the initial volume

$T_1 = 0^{\circ}=273 K$ is the initial temperature (stp temperature)

$p_2 = 368 torr = 4.9\cdot 10^4 Pa$ is the final pressure

$V_2 = ?$ is the final volume

$T=155^{\circ}=428 K$ is the final temperature

By substituting the numbers inside the formula and solving for V2, we find the final volume:

$V_2 = \frac{p_1 V_1 T_2}{T_1 p_2}=\frac{(1.01\cdot 10^5 Pa)(7.46\cdot 10^{-4} m^3)(428 K)}{(273 K)(4.9\cdot 10^4 Pa)}=2.41\cdot 10^{-3} m^3$

which corresponds to 2.41 L.

7 0

3 years ago

A 0.15 kg baseball is hit by a baseball bat. Right before it is hit, the ball’s speed is 30 m/s, and right after it is hit, the

Roman55 [17]

Answer:

Impulse will be 12 kgm/sec

So option (b) will be correct option

Explanation:

We have given mass of the baseball m = 0.15 kg

Ball speed before hit $v_1=30m/sec$

Ball speed after hitting $v_2=-50m/sec$ ( negative direction due to opposite direction )

We have to find the impulse

We know that impulse is equal; to the change in momentum

So change in momentum = $m(v_1-v_2)=0.15(30-(-50))=0.15\times 80=12kgm/sec$

So option (b) will be correct option

5 0

3 years ago

Explain how you think humans have disrupted the nitrogen cycle HELP QUICK DUE APRIL 15TH ANYBODY

mina [271]

Answer:

Scientists have determined that humans are disrupting the nitrogen cycle by altering the amount of nitrogen that is stored in the biosphere. The chief culprit is fossil fuel combustion, which releases nitric oxides into the air that combine with other elements to form smog and acid rain.

5 0

2 years ago