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3 years ago

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which statement best describes an asteroid? A. large chunks of rock with many craters that orbit the sun. B. Pieces of rock or d

ust that shine or flicker in the earth's atmosphere. C. An object made of ice, gas, and dust that orbits the earth. D. Large chunks of rock with bright tails that orbits the sun.

1 answer:

BigorU [14]3 years ago

8 0

Answer:

The answer is A.

Explanation:

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Mr Yadav buys a radio for Rs 640 and sells it for Rs 672 Find it's profit<br><br>

Arisa [49]

Answer:

32

Explanation:

672-640=32

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3 years ago

What happens during a solar eclipse

DENIUS [597]

A solar eclipse occurs when the moon passes directly between the sun and Earth. A total solar eclipse<span> occurs when the sun, moon and Earth are in direct line, and the moon casts a large shadow onto Earth’s surface.

Credit to: Channel One News

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3 years ago

Read 2 more answers

Using the solubility curvechoose all of the statements that are correct

motikmotik

Explanation:

where are the statements

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3 years ago

An ideal Otto cycle has a compression ratio of 8. At the beginning of the compression process, air is at 95 kPa and 27°C, and 75

katen-ka-za [31]

Answer:

Part A) 3899 kPa

Part B) 392.33 kJ/kg

Part C) 0.523

Part D) 495 kPa

Explanation:

Part A

First from the temperature at state 1 the relative specific volume and the internal energy at that state are determined from:

$u_{1}$ = 214.07 kJ/kg

$\alpha$ $r_{1}$ = 621.2

The relative specific volume at state 2 is obtained from the compression ratio:

$\alpha$ $r_{2}$ = $\frac{\alpha r_{1} }{r}$

=621.2/ 8

= 77.65

From this the temperature and internal energy at state 2 can be determined using interpolation with data from A-17(table):

$T_{2}$ = 673 K

$u_{2}$ = 491.2 kJ/kg

The pressure at state 2 can be determined by manipulating the ideal gas relations at state 1 and 2:

$P_{2}$ = $P_{1} r\frac{T_{2} }{T_{1} }$

= 95*8*673/300

= 1705 kPa

Now from the energy balance for stage 2-3 the internal energy at state 3 can be obtained:

$deltau_{2-3} =q_{in}\\ u_{3} -u_{2} =q_{in}\\u_{3}=u_{2}+q_{in}$

= 1241.2 kJ/kg

From this the temperature and relative specific volume at state 3 can be determined by interpolation with data from A-17(table):

$T_{3}$ = 1539 K

$\alpha r_{3}$ = 6.588

The pressure at state 3 can be obtained by manipulating the ideal gas relations for state 2 and 3:

$P_{3} =P_{2} \frac{T_{3} }{T_{2} }$

= 3899 kPa

<u>Part B</u>

The relative specific volume at state 4 is obtained from the compression ratio:

$\alpha r_{4}= r\alpha r_{3}$

= 52.7

From this the temperature and internal energy at state 4 can be determined by interpolation with data from A-17:

$T_{4}$ =775 K

$u_{4}$ = 571.74 kJ/kg

The net work output is the difference of the heat input and heat rejection where the heat rejection is determined from the decrease in internal energy in stage 4-1:

$w=q_{in}-q_{out}\\q_{in}-(u_{4} -u_{1} )\\=392.33 kJ/kg$

<u>Part C </u>

The thermal efficiency is obtained from the work and the heat input:

η= $\frac{w}{q_{in} }$

=0.523

<u>Part D </u>

The mean effective pressure is determined from its standard relation:

MEP= $\frac{w}{\alpha_{1}- \alpha_{2} }$

= $\frac{w}{\alpha_{1}(1- \frac{1}{r} }$

= $\frac{rwP_{1} }{RT_{1} (r-1) }$

=495 kPa

8 0

4 years ago

You are going to speak to a group of your peers on the dangers of drinking and driving. As you prepare your talk, you need to co

enyata [817]

Teens drink mostly because the people/media around them tell them its "cool" and to be liked you have to drink, or "why miss out on the fun?" "Are you scared?" They are pressured into the idea that if they want to be cool or liked, they need to drink.
I'm not in Florida, so I wouldn't know your specific laws, but I know that driving under the influence is pretty much illegal in every state, and you will have consequences if you are caught.
Hope this helps!

3 0

4 years ago