A cargo spacecraft was orbiting the earth. It is equipped with rocket and has an initial mass of 30 metric ton. It wants to catch up with the international space station to deliver the cargo. So its rocket engine was fired for 1 minute. The engine ejects mass at a rate of 30 kg/s with an exhaust velocity of 3.1 km/s. The pressure at the nozzle exit is 5 kPa and the diameter of exit area is 94.4 cm. What is the thrust of the engine in a vacuum

Answers

Answer 1

Answer:

Explanation:

A cargo spacecraft was orbiting the earth. It is equipped with rocket and has an initial mass of 30 metric ton. It wants to catch up with the international space station to deliver the cargo. So its rocket engine was fired for 1 minute. The engine ejects mass at a rate of 30 kg/s with an exhaust velocity of 3.1 km/s. The pressure at the nozzle exit is 5 kPa and the diameter of exit area is 94.4 cm. What is the thrust of the eng


Related Questions

A total charge of 9.0 mC passes through a cross-sectional area of a nichrome wire in 3.6s. The number of electrons passing through the cross-sectional area in 10s is

Answers

Given :

total charge = 9.0 mC = 0.009 C

Each electron has a charge of :

[tex]1.6 \times 10 {}^{ - 19} \: C[/tex]

For producing 1 Cuolomb charge we need :

[tex] \mathrm{\dfrac{1}{1.6 \times 10 {}^{ - 19} } }[/tex]

[tex] \dfrac{10 {}^{19} }{1.6} [/tex]

[tex] \dfrac{10\times 10 {}^{19} }{16} [/tex]

[tex] \dfrac{100 \times 10 {}^{18} }{16} [/tex]

[tex] \mathrm{6.24 \times 10 {}^{18} \: \: electrons}[/tex]

Now, for producing 0.009 C of charge, the number of electrons required is :

[tex]0.009 \times 6.24 \times {10}^{18} [/tex]

[tex]0.05616 \times 10 {}^{18} [/tex]

[tex] \mathrm{5.616 \times 10 {}^{16} \: \: electons}[/tex]

_____________________________

So, Number of electrons passing through the cross section in 3.6 seconds is :

[tex] \mathrm{5.616 \times 10 {}^{16} \: \: electrons} [/tex]

Number of electrons passing through it in 1 Second is :

[tex] \dfrac{5.616 \times {10}^{16} }{3.6} [/tex]

[tex] \mathrm{1.56 \times 10 {}^{16} \: \: electrons}[/tex]

Now, in 10 seconds the number of electrons passing through it is :

[tex]10 \times \mathrm{1.56 \times 10 {}^{16} \: \: }[/tex]

[tex] \mathrm{1.56 \times 10 {}^{17} \: \: electrons}[/tex]

_____________________________

[tex]\mathrm{ \#TeeNForeveR}[/tex]

A playground merry-go-round with a radius of 2.0 m and a rotational inertia of 100 kg m2 is rotating at 3.0 rad/s. A child with a mass of 22 kg jumps onto the edge of the merry-go-round, traveling radially inward. What is the new angular speed of the merry-go-round

Answers

Answer:

The new angular speed of the merry-go-round = [tex]1.6rad/sec[/tex]

Explanation:

From angular momentum conservation

[tex]Iw_1 = (I + mr^2)w_2\\\\3*100 = (100 + 22*2^2)w_2\\\\300 = (100 + 88)w_2\\\\w_2 = \frac{300}{188}\\\\w_2 = 1.6rad/sec[/tex]

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map.
Which best describes the motion of the object
between 1 and 4 seconds?
کے م
The object has decreasing acceleration and
increasing velocity.
The object has positive acceleration and eventually
stops.
The object has decreasing acceleration and
decreasing velocity.
The object has negative acceleration and eventually
stops.

Answers

Answer:

The object has decreasing acceleration and decreasing velocity.

if an object sinks in water its density is greater than that of water

Answers

I think this is true but sorry if that’s wrong. Hope this helps :-)
Density is a measure of how heavy something is compared to its size. If an object is more dense than water it will sink when placed in water, and if it is less dense than water it will float.

A charged rod is brought near one end of a long, uncharged metal block. Students want to experimentally measure the resulting charge distribution along the entire length of the block. They have a small, positively charged sphere on a string that can be used as a test charge with negligible effect on the other charges. They will observe whether the sphere is attracted or repelled when held near the rod. Which of the following describes and justifies a procedure that will provide data to determine the entire charge distribution?

a. Hold the sphere near the end of the block closest to the rod, because that will give experimental data about both ends of the block.
b. Hold the sphere near each end of the block, because that will give experimental data about both ends of the block.
с. Hold the sphere near each end of the block and near the block's middle, because that will give experimental data about the area along the length of the block.
d. Hold the sphere near each end of the block and at a number of points along the length of the block, because that will give experimental data for the whole block.

Answers

Answer:

d

Explanation:

The sphere is positively charged so that when it comes in contact with the rod, its positive charges will repel to the other end. Hence, Hold the sphere near each end of the block, because that will give experimental data about both ends of the block.

What is polarization?

Polarization is the separation of charges into two poles due electrostatic repulsion. Two similar charges will repel and opposite charges attracts each other.

When a charged or polar substance get in contact with a non-polar substance, the nonpolar one will deform in such a way that the electrons from the polar one will repel the electrons of nonpolar and there occurs a temporary charge separation in non polar substance creating an induced polarity.

Here, when the positive sphere comes in contact with the charged rod, the positive charges will align to the opposite pole of the rod away from the sphere and the negative charges will align near the sphere.

Thus there occurs an attractive force at one end and repulsion at the other end. Thus, holding the sphere at each end will data about charge distribution.

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Which of the following does NOT create a mechanical wave? Text to speech
A. a shaking rope
B. a guitar being played
C. dropping a rock in a pond
D. light coming through a window

Answers

light coming through a window!!

Answer:

light coming through a window

What is this answer? A blank is a combination of two or more substances, elements, compounds, or both, in the same place but not chemically combined

Answers

A mixture? lmk if that’s the right answer! your welcome :)

3. What is the force of sliding friction
between a block and the ground if the
coefficient of kinetic friction is uk = 0.17
and the block weighs 18 N?
a. 0.52 N
b. 55 N
C. 18 N
d. 3.1 N

Answers

Answer:

the force of the friction is A-0.52

URGENT: Testing shows that a sample of wood from an artifact contains 50% of the
original amount of carbon-14. Given that the half-life of carbon-14 is 5730
years, how old is the artifact?
O A. 22,920 years
B. 11,460 years
C. 5730 years
O D. 2865 years

Answers

Answer:

Im so so sorry but I do now know how to do this

Explanation:

A 0.454-kg block is attached to a horizontal spring that is at its equilibrium length, and whose force constant is 25.0 N/m. The block rests on a frictionless surface. A 5.70×10−2-kg wad of putty is thrown horizontally at the block, hitting it with a speed of 8.99 m/s and bounced with the same speed of 8.99 m/s in opposite direction. How far does the block compresses the spring?

Answers

The total momentum of the block and putty prior to their collision is

(0.454 kg) (0 m/s) + (5.70 × 10⁻² kg) (8.99 m/s) ≈ 0.512 kg•m/s

and the total momentum after the collision is

(0.454 kg) v + (5.70 × 10⁻² kg) (-8.99 m/s)

where v is the velocity of the block. Momentum is conserved, so

(0.454 kg) v + (5.70 × 10⁻² kg) (-8.99 m/s) = 0.512 kg•m/s

==>   v ≈ 2.26 m/s

The total work done on the block by the spring as it gets compressed by a distance x is equal to the change in the block's kinetic energy:

1/2 (25.0 N/m) x ² = 1/2 (0.454 kg) (2.26 m/s) - 0

==>   x ≈ 0.202 m ≈ 20.2 cm

Show that if you have three polarizing filters, with the second at an angle of 45 degrees to the first and the third at an angle of 90 degrees to the first, the intensity of light passed by the first will be reduced to 25% of its value. (This is in contrast to having only the first and third, which reduces the intensity to zero, so that placing the second between them increases the intensity of the transmitted light.)

Answers

Answer:

  I₃ /I₀ = 25%

Explanation:

For this exercise let's use Malus's law

         I = I₀ cos² θ

where tea is the angle between the two polarizers.

When the polarized light passes the first polarizer, the intensity is constant if it is in the direction of polarization.

        I₁ = I₀

the light transmitted by the second polarizer is

        I₂ = I₁ cos² θ

        I₂ = I₀ cos² 45

        I₂ = I₀ 0.5

this light is polarized 45º with respect to the first polarizer

Now let's examine the third polarizer, it is indicated that it has an angle of 90º with respect to the first polarizer, the angle with respect to the second polarizer is

        θ = 90 - 45

        θ = 45º

so the polarizer is at an angle of 45º

let's use Maus's law

         I₃ = I₂ cos² 45

         I₃ = I₀ 0.5 cos² 45

         I₃ = I₀ 0.25

the light that passes through the system is

         I₃ /I₀ = 0.25

as a percentage we multiply by 100

         I₃ /I₀ = 25%

Hello guys sana ok lng kau​

Answers

sssssssssssss

Explanation:

Answer:

hello how are you

have a great day

What happened to the combined energy of the two sleds when they collided?

Answers

Hi!
Here’s your answer:

What happened to the combined energy of the two sleds when they collided? It changed forms into another energy C. Because energy is conserved, the “lost” energy has actually been changed into other forms.

Hope this helps have a good day!!<3

Combined energy of the two sleds will be conserved when they collides.

What is Energy ?

Energy is nothing but the ability to do work. there are different energies in different form which are thermal energy, mechanical energy, electric energy and sound energy etc.

According to first law of thermodynamic, Energy neither be created nor be destroyed. it can only be transferred from one form into another form. Energy is expressed in joule (J). its dimensions are [M¹ L² T⁻²].

Energy is conserved throughout the motion,

according to conservation law of energy, initial energy is equal to final energy.

When two sleds coming in opposite direction, it is having mass as well as velocity. hence it has kinetic energy, when they get collide with each other some of total energy gets converted into sound energy as collision cause sound(boom). some of the energy will use to break the material which made the sled and remaining energy will convert in kinetic energy of broken sleds it can be moved in opposite direction or in same direction depending initial energies.

in this collision combined kinetic energy can be converted into sound energy, mechanical energy and again kinetic energy but totally energy is conserved.

Hence combined energy will be conserved.

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How were the barriers to critical thinking presented?

Answers

Answer:

At a personal level, barriers to critical thinking can arise through: ... self-centred or societal/cultural-centred thinking (conformism, dogma and peer-pressure) unconscious bias, or selective perception. an inability to be receptive to an idea or point of view that differs from your own (close-mindedness)

Explanation:

Science questions!! Please help!!
Post Assessment on Investigating the Immune System
please help!! Please choose the right answers!! Dont guess if you dont know the answers!!

Answers

9: A
10: A
11: D
12: A
13: D
14: B
15: A.

Can you please mark me brainliest THANKS
hope this helped

⦁ Light coming from a fish makes an incidence angle of 30° to normal under the water. The index of refraction of water is 1.33. A fisherman is looking at the fish through air. At what angle with the normal will the fish appear to the fisherman? Use Snell’s law: .

Answers

Answer:

snell's law = sinI /sin r

refractive index = sinI /sin r

1.33= 30 /sinR

sinR= 1.33×30

sinR=39.9

The angle with the normal by which the fish appear to the fisherman is 41.68 degrees.

What is Snell's law?

According to the Snell's law, the ratio of index of reflection of the different material is equal to the ratio of incident sine angle and reflective sine angle. It can be given as,

[tex]\dfrac{n_1}{n_2}=\dfrac{\sin\theta_2}{\sin\theta_1}[/tex]

Here (n₁ and n₂) are the index and reflective index and (θ₁ and θ₂) are the incident and reflected angle.

Light coming from a fish makes an incidence angle of 30° to normal under the water. The index of refraction of water is 1.33. A fisherman is looking at the fish through air.

The index of refraction of air is 1. Thus, by the Snell's law,

[tex]\dfrac{1}{1.33}=\dfrac{\sin(30)}{\sin\theta_1}\\\theta_1=41.68^o[/tex]

Thus, the angle with the normal by which the fish appear to the fisherman is 41.68 degrees.

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Which statement best describes covalent bonding?
A. two nonmetal atoms share electrons between them
B. many atoms give up electrons that can move among the atoms
C. two metal atoms share electrons between them
D. a metal atom transfers electrons to a nonmetal atom

Answers

A. Two nonmetal atoms share electrons between them. I’m taking chemistry, so i know.

The Moon is attracted to the Earth. The mass of the Earth is 6.0x1024 kg and the mass of the Moon is 7.4x1022 kg. If the Earth and Moon are 345,000 km apart, what is the gravitational force between them?

Answers

Sorry I don't know the answer

What is the acceleration of a bicycle that goes from 3 m/s to 1 m/s in 2 seconds?
0.5 m/s2
1.0 m/s2
1.5 m/s2
-1.0 m/s2

Answers

Answer:

a=vf - vi/t

vf=final velocity

vi= initial velocity

t=time period

Now The bicycle went from 3ms to 1ms...

1.. It decelerated

2... Since it went from 3 to 1... 1 is the final velocity while 3 is the initial Velocity

Applying the Formula

a= 1-3/2

= -2/2

a= -1ms-²

Option D

6. A lumberjack is standing on a log floating on a lake. She starts from rest, then runs along the log to the end, when she jumps from the first log onto a second. After landing safely on the second log, she slows down and ends up standing on the second log. Both logs both have masses of 150 kg each and the mass of the lumberjack is 70 kg. The lumberjack reaches a speed of 7.0 m/s relative to the shore during her jump. What are the speeds of the two logs and of the lumberjack after she has stopped on the second log

Answers

Answer:

a) -3.267 m/s

b) 2.227 m/s

Explanation:

As per the conservation of momentum

m1v1 + m2v2=0

m1= mass of log

m2 = mass of lumber jack

v1 = velocity of log

v2 = velocity of lumber jack

a) Velocity of first log

[tex]-\frac{70*7}{150} = -3.267[/tex] m/s

b) m1v1 + m2v2 = m3v3

Velocity of log

= [tex]\frac{70*7}{150+70} \\2.227[/tex]

Two creatures sit on a horizontal frictional rotating platform. The platform rotates at a constant speed. The creatures do not slip off as it rotates.


ASSUME:

Red has a mass of 5 kg

Red is 1.5 m from the center

Red has a speed of 9 m/s

Blue has a mass of 25 kg

Blue has a speed of 1.8 m/s

The force of friction on Red is EQUAL to the force of friction on Blue





DETERMINE:

How far from the center is Blue

Answers

Answer:

M v^2 / R = centripetal force

For Red: M v^2 / R = 5 * 9^2 / 1.5 = 270

For Blue M v^2 / R = 270 = 25 * 1.8^2 / Rb

So Rb = 25 * 1.8^2 / 270 = .3 m

3.Which of the following is a derived physical quantitySingle choice.


Length

Mass

Stress

Time​

Answers

Answer:

length

Explanation:

Legth is derived physical quantity

Light is traveling in glass, and hits a glass/unknown surface. In the glass the light beam is making an angle of 45.0 o with the normal to the surface. The glass has an index of refraction of 1.52. (A) If the refracted light ray leaves the glass at an 55o from the normal, what is the index of refraction for the unknown surface

Answers

Answer:

n = 1.31

Explanation:

When a ray of light crosses the separation surface between two transparent media, there exists a fixed relationship between the indexes of refraction of both media, related with the angles of incidence and refraction, which is known as Snell's Law.The Snell's Law can be written as follows:

        [tex]n_{i} * sin( \theta_{i}) = n_{r} * sin( \theta_{r}) (1)[/tex]

In our case the ray is incident from the glass, so ni = n glass = 1.52The angle of incidence is the angle that the ray makes with the normal to the separation surface, so θi=45º.The angle of refraction is the angle that the refracted ray makes with the normal, so θr= 55ºReplacing by the values in (1), and solving for nr, we have:

       [tex]n_{r} =\frac{n_{i} * sin \theta_{i} }{sin \theta_{r} } = \frac{sin (45)*1.52}{sin (55)} = 1.31 (2)[/tex]

Polarizing windows, filters, etc. are often used to reduce the amount of light that enters the lens of a camera or into a room or a car. A library atrium has an overhead skylight that lets in too much light during the day which heats up the interior of the library far too much. The building engineer installs new double paned polarizing sky lights to reduce the intensity. If sunlight, which is unpolarized, has an average intensity of 1366 W/m2 what angle should the polarizing axis of the second pane of the window make with the polarizing axis of the first pane of the window in order to reduce the intensity of the sunlight to 33% of the original value

Answers

Answer:

 θ = 35.7º

Explanation:

For this exercise we must use the law of Malus

          I = I₀ cos² θ

where the angle is between the two polarizers.

When the unpolarized light from the sun reaches the first polarizer, only the light polarized in the direction manages to be transmitted, which is why

          I₁ = I₀ /2

this light reaches the second polarizer

           I₂ = I₁ cos² θ

           I₂ = I₀/2    cos² θ

           cos² θ = 2 I₂ / Io

indicate that the transmitted light is 33% = 0.33 I₀

          cos² θ = 2 0.33

          cos θ = √0.66

          θ = cos⁻¹ 0.8124

          θ = 35.7º

distance moved by the effort in lifting the 5000N load to the height of 15m

Answers

Answer:

Hello There!!

Explanation:

Work done= force × distance moved

Work done=5000N×15m

Work done=75,000J

hope this helps,have a great day!!

~Pinky~

g 2. In a laboratory experiment on standing waves a string 3.0 ft long is attached to the prong of an electrically driven tuning fork which vibrates perpendicular to the length of the string at a frequency of 60 Hz. The weight (not mass) of the string is 0.096 lb. a) [5 pts] What tension must the string be under (weights are attached to the other end) if it is to vibrate in four loops

Answers

Answer:

The tension in string will be "3.62 N".

Explanation:

The given values are:

Length of string:

l = 3 ft

or,

 = 0.9144 m

frequency,

f = 60 Hz

Weight,

= 0.096 lb

or,

= 0.0435 kgm/s²

Now,

The mass will be:

= [tex]\frac{0.0435}{9.8}[/tex]

= [tex]0.0044 \ kg[/tex]

As we know,

⇒  [tex]\lambda=\frac{2L}{n}[/tex]

On substituting the values, we get

⇒     [tex]=\frac{2\times 0.9144}{4}[/tex]

⇒     [tex]=0.4572 \ m[/tex]

or,

⇒  [tex]v=f \lambda[/tex]

⇒      [tex]=0.4572\times 60[/tex]

⇒      [tex]=27.432 \ m/s[/tex]

Now,

⇒  [tex]v=\sqrt{\frac{T}{\mu} }[/tex]

or,

⇒  [tex]T=\frac{m}{l}\times v^2[/tex]

On putting the above given values, we get

⇒      [tex]=\frac{0.0044}{0.9144}\times (27.432)^2[/tex]

⇒      [tex]=\frac{752.51\times 0.0044}{0.9144}[/tex]

⇒      [tex]=3.62 \ N[/tex]

An electron is accelerated through 1.90 103 V from rest and then enters a uniform 1.80-T magnetic field.
(a) What is the maximum magnitude of the magnetic force this particle can experience?

Answers

Answer:

https://www.slader.com/discussion/question/an-electron-is-accelerated-through-240-times-103-v-from-rest-and-then-enters-a-uniform-170-t-magnetic-field-what-are-a-the-maximum-and-b-the-9e425fbd/

( Here is solution)

Which of the following is a terrestrial habitat?
A) Pond B) Garden C) Lake D) River​

Answers

Answer:

garden

Explanation: All the other habitats are aquatic

Which of the following describes an electric insulator?
O A. A material that has a low resistance and prevents charges from
moving freely
B. A material that has a low resistance and allows charges to move
freely
C. A material that has a high resistance and prevents charges from
moving freely
D. A material that has a high resistance and allows charges to move
freely

Answers

The following that describes an electric insulator are :

C. A material that has a high resistance and prevents charges from  moving freely.    

The following that describes an electric insulator is a material that has a high resistance and prevents charges from  moving freely.  The conductors exhibit low resistance, which allows for the flow of current through it freely.  

Thus, the correct answer is C.

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Coherent light with wavelength 591 nm passes through two very narrow slits, and the interference pattern is observed on a screen a distance of 3.00 m from the slits. The first-order bright fringe is a distance of 4.84 mm from the center of the central bright fringe. For what wavelength of light will the first-order dark fringe be observed at this same point on the screen?

Answers

Answer:

The wavelength will be "1.182 μm".

Explanation:

The given values are:

Wavelength

[tex]\lambda=591 \ nm[/tex]

or,

  [tex]=591\times 10^-9 \ m[/tex]

Distance,

[tex]d = 3.00 m[/tex]

[tex]n = 1[/tex]

Distance of fringe from center,

[tex]y = 4.84 \ mm[/tex]

We have to find the wavelength of first order dark fringe,

[tex]\lambda = ?[/tex]

As we know,

⇒ [tex]y_{bright} =\frac{1\times \lambda\times L}{d}[/tex]

On putting the given values in the formula, we get

   [tex]0.00484=\frac{1\times (591\times 10^{-9})\times 3}{d}[/tex]          

On applying the cross multiplication, we get

   [tex]\lambda = \frac{0.00484\times 000036632}{0.5\times 3}[/tex]

      [tex]=1182\times 10^{-9}[/tex]

or,

      [tex]=1.182 \ \mu m[/tex]    

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