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3 years ago

11

Beginning with earth, summarize the structure of the universe. Also Andromeda galaxy is located appromaxily 2.5 million light-ye

ars from earth. Why is the light that reaches earth 2.5 million years old. So many points look.

1 answer:

Leokris [45]3 years ago

4 0

Because of the power of the light it is very strong so that is why light reaches all the way to earth

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Based on its type of chemical bond, which of the following has the highest boiling point?

Sever21 [200]

<h3><u>Answer;</u></h3>

Potassium chloride

<h3><u>Explanation;</u></h3>

Potassium Chloride is an ionic compound and has ionic bond which is stronger than covalent bond in ethyl alcohol,water ,ammonia, and thus has the highest boiling point .
ionic bond is a type of bond that results from the transfer of electrons between metallic atoms and non-metallic atoms.

5 0

3 years ago

Steam is to be condensed on the shell side of a heat exchanger at 150 oF. Cooling water enters the tubes at 60 oF at a rate of 4

zalisa [80]

Answer:

a. 572Btu/s

b.0.1483Btu/s.R

Explanation:

a.Assume a steady state operation, KE and PE are both neglected and fluids properties are constant.

From table A-3E, the specific heat of water is $c_p=1.0\ Btu/lbm.F$ , and the steam properties as, A-4E:

$h_{fg}=1007.8Btu/lbm, s_{fg}=1.6529Btu/lbm.R$

Using the energy balance for the system:

$\dot E_{in}-\dot E_{out}=\bigtriangleup \dot E_{sys}=0\\\\\dot E_{in}=\dot E_{out}\\\\\dot Q_{in}+\dot m_{cw}h_1=\dot m_{cw}h_2\\\\\dot Q_{in}=\dot m_{cw}c_p(T_{out}-T_{in})\\\\\dot Q_{in}=44\times 1.0\times (73-60)=572\ Btu/s$

Hence, the rate of heat transfer in the heat exchanger is 572Btu/s

b. Heat gained by the water is equal to the heat lost by the condensing steam.

-The rate of steam condensation is expressed as:

$\dot m_{steam}=\frac{\dot Q}{h_{fg}}\\\\\dot m_{steam}=\frac{572}{1007.8}=0.5676lbm/s$

Entropy generation in the heat exchanger could be defined using the entropy balance on the system:

$\dot S_{in}-\dot S_{out}+\dot S_{gen}=\bigtriangleup \dot S_{sys}\\\\\dot m_1s_1+\dot m_3s_3-\dot m_2s_2-\dot m_4s_4+\dot S_{gen}=0\\\\\dot m_ws_1+\dot m_ss_3-\dot m_ws_2-\dot m_ss_4+\dot S_{gen}=0\\\\\dot S_{gen}=\dot m_w(s_2-s_1)+\dot m_s(s_4-s_3)\\\\\dot S_{gen}=\dot m c_p \ In(\frac{T_2}{T_1})-\dot m_ss_{fg}\\\\\\\dot S_{gen}=4.4\times 1.0\times \ In( {73+460)/(60+460)}-0.5676\times 1.6529\\\\=0.1483\ Btu/s.R$

Hence,the rate of entropy generation in the heat exchanger. is 0.1483Btu/s.R

4 0

4 years ago

A teacher did an experiment to show the movement of particles in solids, liquids, and gases. The experimental set-up is shown be

ELEN [110]

Answer: Option (B) is the correct answer.

Explanation:

In a solid, molecules are held together by strong intermolecular forces of attraction. As a result, they are unable to move from their initial place but they can vibrate at their mean position.

Hence, in solid substances the molecules have low kinetic energy.

Whereas in liquids, the molecules are held by less strong intermolecular forces of attraction as compared to solids. Due to which they are able to slide past each other. Hence, they have medium kinetic energy.

In gases, the molecules are held by weak Vander waal forces. Hence, they have high kinetic energy due to which they move rapidly from one place to another leading to more number of collisions.

Hence, gases are able to expand more rapidly as compared to liquids.

Thus, we can conclude that out of the given options solid = low; liquid = medium; gas = high, combination of the state of matter and the corresponding dryer speed is correct.

8 0

4 years ago

Two satellites have circular orbits with the same radius. Which has a higher speed? One satellite has more mass and the other ha

RideAnS [48]

The satellite with more mass will definitely have a higher speed. The correct option among all the options that are given in the question is the first option. Although the satellite having more mass should have a larger mass difference to have a noticeable speed change. Otherwise it would be hard to detect the speed change. Also we know that
orbit speed = proportional to square root[(Mass of Earth + Mass of Satellite)/orbit radius]. This explains the answer. <span />

3 0

3 years ago

Read 2 more answers

A tuning fork produced four beats per second with a second, 270-Hz tuning fork. What are the two possible frequencies of the fir

EleoNora [17]

Answer:

frequency of the first tuning fork can be 274 Hz or 266 Hz

Explanation:

Given data :

we have number of beats per second = 4

thus, it can also be written as

Beat frequency of the tuning fork, v = 4 Hz

Frequency of the tuning fork, f = 270 Hz

now, the beat frequency is actually the difference of the consecutive frequency.

thus, we have

Frequency of the first tuning fork as = 270 Hz + 4 Hz = 274 Hz

or

Frequency of the first tuning fork as = 270 Hz - 4 Hz = 266 Hz

Therefore, the frequency of the first tuning fork can be 274 Hz or 266 Hz

7 0

3 years ago