What was the name of the voyages taken by Zheng he during the Ming dynasty on behalf of China

Answers

Answer 1

Answer:

Ming treasure voyages

Explanation:


Related Questions

Ice is placed in cool water. What happens to the temperature of the ice and the water?

Answers

Answer:

Explanation:

ice absorbs heat from the water. As the water molecules lose energy, they begin to slow down, and consequently to cool. So, it's kind of the opposite of what we might think: when we put ice in water, the ice doesn't give its cold to the water, it takes heat from the water.

What are the functionsssss of geostationary satellite and non-geostationary satellite?​

Answers

Answer:

What is the difference between a geostationary satellite and a non-geostationary satellite? Geostationary (GSO) satellites occupy an orbital position 36,000 km above the earth, and remain in a stationary position relative to the Earth itself.

a test tube has a diameter of 3cm . how many turns would a piece of thread of length 90.42 make round test tube​

Answers

Answer:

4.8 turns would be made around the tube

Explanation:

You need the circumference of the tube since it's just a lifted circle

2×pi×3=18.85

90.42/18.85=4.79

And round that to 4.8

Help pls... 100points
1 Answer:
The pitch of a sound depends on
a. frequency
b. intensity
c. amplitude
d. quality
2 Answer:
The loudness of a sound depends on
a. frequency
b. intensity
c. overtones
d. timbre
3 Answer:
The number of sound waves per unit time is called
a. amplitude
b. wavelength
c. speed
d. frequency
4 Answer:
The blending of fundamental tone and overtones produces a sound's
a. intensity
b. pitch
c. timbre
d. loudness
5 Answer:
Sonar is used
a. to locate objects in water
b. to determine underwater distances
c. for both a and b
d. for neither a nor b
6 Answer:
Sounds of frequencies below 20 Hz are called
a. fundamentals
b. overtones
c. ultrasonic sounds
d. infrasonic sounds
7 Answer:
A sound is music if it has
a. a definite pitch
b. a pleasing quality
c. rhythm
d. all of these characteristics
8 Answer:
The stirrup is a part of the
a. outer ear
b. middle ear
c. inner ear
d. cochlea
9 Answer:
An example of a percussion instrument is a (an)
a. trumpet
b. harp
c. drum
d. flute
10 Answer:
The speed of sound depends on
a. temperature
b. density
c. elasticity
d. all of these factors
11 Answer:
Sounds with frequencies above 20,000 Hz are called _____.
12 Answer:
The science of sound is called _____.
13 Answer:
High-frequency waves are used in a sound navigation and ranging
system called _____.
14 Answer:
Sounds produced when sections of a string vibrate separately are
called _____.
15 Answer:
Sound without pleasing quality, identifiable pitch, and repeating
patterns is called _____.
16 Answer:
The speed of sound decreases with increasing temperature.
a. true
b. false
17 Answer:
Sound waves are transverse.
a. true
b. false
18 Answer:
The decibel is a unit of pitch.
a. true
b. false
19 Answer:
A change in the pitch of a sound due to motion of source or
receiver (observer) is called the Doppler effect.
a. true
b. false
20 Answer:
Guitars and cellos are examples of percussion instruments.
a. true
b. false

Answers

Answer:

Explanation:

1. a as pitch depends on frequency

2. b as loudness depends on intensity

3. d as that is definition of frequency

4. c as that is definition of timbre

5. c as sonar can do both

6. d as that is definition of infrasound

7. d

8. b as that is one of three bones in the middle ear

9. c as you hit the drum to make sound

10. d

11. ultrasound

12. acoustics

13. ultrasound

14.  harmonics? or resonance?

15. noise

16. b

17. b

18. b

19. a

20. b

why do trucks need a runaway ramp

Answers

Answer:

in case they lose control going downhill.

Explanation:

which is why they usually have a steep incline and are quite long. You see them used typically when the trucks brakes fail.

Which best describes a tsunami?

Answers

Answer:

A tsunami is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water.

Answer:

A tsunami is series of waves caused by heavy winds. Hurricanes can cause tsunami

Explanation:

To understand the first law of thermodynamics and its origin. By relating heat, thermal energy, and work, the first law lays the groundwork for thermodynamics. The first law of thermodynamics generalizes the concept of energy conservation to include heat energy. You are probably already aware that loss of total mechanical energy (e.g., from nonconservative forces such as friction) does not destroy energy, but rather converts mechanical energy into thermal energy. This process, as well as the reverse process (conversion of thermal energy into mechanical energy), can be described quantitatively by the first law. Like the law of mechanical energy conservation that it generalizes, the first law relates the changes in energy that occur from the beginning to the end of some process. The first law involves the following physical quantities Using your knowledge of energy conservation, express AEth in terms of Q and W. • W: work done on the system by the outside world, Q: heat added to the system by the outside world, and AEth: thermal energy change of the system.

Answers

Answer:

okay

Explanation:

Your _________ is simply your weight-to-height ratio which can be calculated using certain body measurements.

O health
O size
O weight loss
O BMI

Answers

The answer would be Size

Answer:

SiZe

Explanation:

bad bunny is the best!!!

A grindstone in the shape of a solid disk has a shaft attached to allow a force to be exerted on. The grindstone has a diameter of 0.650m and a mass of 55.0 kg. The shaft is 0.300 m from the center of the stone and has a mass of 4.00 kg. The grindstone has a motor attached and it is rotating at 450rev/min at a run when the motor is shut off. The grindstone comes to rest in 9.50 s.
a. What is the moment of inertia of the grindstone including the shaft?
b. What is the angular acceleration of the grindstone?
c. What average torque is done by friction to bring the grindstone to rest?
d. How many revolutions has it taken the grindstone to come to rest?
e. What is the linear acceleration of the shaft in this process?
f. What is the linear distance that the shaft traveled?

Answers

Answer:

a)  3.265 kg-m^2

b)  - 4.96  rad/s^2

c) 16.1944 N-m

d) 35.625

e)  - 1.488 m/s^2

f)  67.1175 m.

Explanation:

Given data:

Diameter of grindstone ( D ) = 0.650 m ,  Radius ( R ) = 0.325 m

mass of grindstone ( M ) = 55 kg

Radius of shaft ( r ) = 0.300 m

mass of shaft ( m ) = 4 kg

Initial Angular velocity = 450 rev/min = f = 7.5 rev/s = w  =15π rad/s

time ( t ) = 9.50 secs

a) Determine the moment of inertia of the grindstone including the shaft

moment of inertia of grindstone = MR^2 / 2 = 55* (0.325)^2 / 2 = 2.905

moment of inertia of shaft = mr^2 = 4 *0.3^2 = 0.36

∴ moment of inertia including shaft = 2.905 + 0.36 = 3.265 kg-m^2

b) Determine the angular acceleration of the grindstone

∝ = - 15π / 9.5 ( i.e.  angular velocity / time )

   = - 4.96  rad/s^2 ( deceleration value )

c) Determine average torque done by friction to bring the grindstone to rest

Torque ( I * ∝ )  = 3.265 x 4.96 = 16.1944 N-m (magnitude)

d) Determine the number of revolutions before grindstone comes to rest

Total revolutions N before grindstone comes to rest

= ( f1 + f2)* t /2 = 7.5 * 9.5 / 2 = 35.625

Note : f2 = 0 as it comes to rest

          f1 = 7.5 rev/s

e) Determine the Linear acceleration of the shaft in this process

This can be calculated using this relation

r * ∝ = 0.3 x (- 4.96 ) = - 1.488 m/s^2

f) Determine the linear distance travelled by the shaft

This can be calculated with the relation below

r * 2 * π * N = 0.3 * 2π * 35.625 = 67.1175 m.

What is meant by density? what are its SI unite?
please answer me..​

Answers

Answer:

Density, mass of a unit volume of a material substance. ... Density offers a convenient means of obtaining the mass of a body from its volume or vice versa; the mass is equal to the volume multiplied by the density (M = Vd), while the volume is equal to the mass divided by the density (V = M/d).

Explanation:

The International System of Units is the modern form of the metric system. It is the only system of measurement with an official status in nearly every country in the world

Answer:

Density is mass per unit volume

Explanation:

SI unit is kgm3

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.

Which of the following creates the night-and-day cycle experienced on Earth?
A) Orbit of Earth around the Sun
B) Rotation of the Sun
C) Rotation of the Earth
D) Tilt of the axis of Earth

Answers

the answer should be C

what types of cuts do jig saw sanders make?​

Answers

The jigsaw can be used to make both straight and curved cuts in a wide variety of materials, including wood, particleboard, plywood, plastic, metal, even ceramic tile. There is also way more than those, but those are just the basics or common things. Hope this helps!

What’s the answer to 19 please please help me

Answers

Answer:

A.

Explanation:

A po sa tingin ko

sana po makatulong

Answer A it transmits red and absorbs all the other colors

2. A company hires a security firm to patrol their stores and watch out for thieves. What is this an example of?

Answers

In a case whereby the company hires a security firm to patrol their stores and watch for thieves, this is an example of Inventory control.

Inventory Control: What Is It?

Inventory control, also known as stock control, is the procedure used to guarantee that a business has the appropriate amount of supplies on hand. As long as internal and production controls are in place, the business can meet client demand and maintain financial flexibility.

The general definition of inventory control or stock control is "the action of verifying a shop's stock." It is the process of making sure that a business has the appropriate amount of supply on hand.

Learn more about Inventory at:

https://brainly.com/question/26533444

#SPJ1

A properly exposed photograph is taken at f/16 and 1/120s. What lens opening is required if the shutter speed is 1/60s

Answers

Answer:

f / 8

Explanation:

The f-number is the ratio of the lens's focal length to its diameter and is a measure of the intensity of the light reaching the CCD. The smaller the greater the intensity of the light

           I = D / f

           f-number = f / D

           I = 1 / f-number

the energy deposited in the CCD is proportional to the intensity of the light and the exposure time (Δt)

          E = I Δt

          E = 1 /f-number   Δt

in the exercise they indicate that the system is well exposed (the image is sharp and clear) for fo-number = f / 16

        Δt = exposure time = 1/120 s

        E =   [tex]\frac{1}{120} \ \ \frac{1}{fo-number}[/tex]  

           

indicate that the exposure time has been changed to Δt = 1/60 s, which should be the f₁-number

        E = [tex]\frac{1}{60} \ \ \frac{1}{f_1-number}[/tex]

the energy deposited must be the same per location we can equal the expressions

          [tex]\frac{1}{120} \ \frac{1}{f_o-number} = \frac{1}{60} \ \frac{1}{f_1-number}[/tex]

         f₁-number = [tex]\frac{60}{120} \ \ \frac{1}{fo-number}[/tex]

         

         f₁-number = ½  16

         f₁-number  = 8

so the system should be set to f / 8

HELP PLZ
A baseball player hits a pop-up. The ball was hit when it was 3 feet off the ground with an initial
upward velocity of 80 ft/s. How long will it take for the ball to reach a height of 10 feet off the
ground, on the way down?

Answers

Answer:

Explanation:

Use the equation

[tex]h(t)=-16t^2+v_0t+h_0[/tex]

where h(t) is the height after a certain amount of time goes by, v0t is the initial upwards velocity, and h0 is the initial height of the projectile. For us:

h(t) = 10

v0t = 80

h0 = 3 and filling in:

[tex]10=-16t^2+80t+3[/tex] and get everything on one side to factor:

[tex]0=-16t^2+80t-7[/tex]

This factors to

t = .09 sec and 4.9 sec. Let's interpret this.

The time of .09 is when the ball reached 10 feet on the way up, and

the time of 4.9 is when the ball reached 10 feet on the way back down. That's the height we need, 4.9 seconds.

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 uniform solid ball has a mass of 20 g and a radius of 5 cm. It rests on a horizontal surface. A sharp force is applied to the ball in the horizontal direction 9 cm above the surface. The force rises linearly from 0 to a peak value of 40,000 N in 10^(-4) s then decreases linearly to 0 in another 10^(-4) s. (The moment of inertia for a solid ball is 2/5 mR^2 ) What is the velocity of the ball after the impact

Answers

Answer:

i think the answer is 32 something

Explanation:

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:

A , D
B , C
C , B
B , D

Answers

Answer:

c and b

Explanation:

hope this helped!

A 16.2-g bullet with an initial speed of 850 m/s embeds itself in a 40.0-kg block, which is attached to a horizontal spring with a force constant of 1000 N/m. What is the maximum compression of the spring

Answers

The maximum compression in the spring is 0.06883 meters.

Given to us,

mass of bullet, [tex]m= 16.2\ grams[/tex]

velocity of bullet, [tex]v= 850\ meter/second[/tex]

mass of the block, [tex]m_2= 40\ kilograms[/tex]

velocity of block, [tex]v_2= 0\ meter/second[/tex]

spring constant, [tex]k = 1000\ Newton/meter[/tex]

Combined mass after collision,

[tex]\begin{aligned}M&= m_1+m_2\\&= 40.0162\ Kilograms\end{aligned}[/tex]

Using the momentum conservation equation, to find out final velocity of the system(bullet and block combined)

[tex]m_1v_1+m_2v_2= MV\\[/tex]

[tex]0.0162\times 850+40\times 0 = 40.0162\times V\\V= 0.3441 meter/sec[/tex]

Now using the Conservation of Energy (Kinetic energy of the system will be equal to potential energy in the spring), to find out the displacement of the spring [tex](x)[/tex]

[tex]\frac{1}{2}kx^2 = \frac{1}{2}MV^2\\\\\frac{1}{2}\times 1000\times x^2= \frac{1}{2} \times40.0162\times0.3441^2\\\\x^2= 0.004738\\\\x= 0.06883\ meters[/tex]

Hence, the maximum compression in the spring is 0.06883 meters.

To know more visit:

https://brainly.com/question/2001019

A nylon rope that has a 0.73 cm radius and is 12 meters long is used to lift a 24 kg object straight up. If the object is lifted at constant velocity, how much is the rope stretched by? The Young's modulus of the nylon is 5.0 × 109 N/m2 and use 9.81 m/s2 for the acceleration of free fall. Express your answer in centimeters and round to the nearest hundredth.

Answers

Answer:

The rope is stretched by 0.3373 cm

Explanation:

As we know  

Youngs Modulus ([tex]5.0 * 10^9[/tex] N/m2) is Stress divided by strain

Stress = force/Area = (65*9.8)/(pi * (7.3*10^-3)^2)

Starin = change in length/original length of the rope = l/12 meters

Substituting the given values we get  

[tex]5.0 * 10^9[/tex] N/m2 = {([tex]\frac{\frac{24*9.8}{\pi *(7.3*10^{-3})^2} }{\frac{\delta L}{L} }[/tex])

[tex]5.0 * 10^9[/tex] N/m2 = {([tex]\frac{\frac{24*9.8}{\pi *(7.3*10^{-3})^2} }{\frac{\delta L}{12} }[/tex])

[tex]\frac{\delta L}{12} = \frac{\frac{65*9.8}{pi * (7.3*10^-3)^2} }{5.0 * 10^9}[/tex]

The rope is stretched by 0.3373 cm

Sources A and B emit long-range radio waves of wavelength 360 m, with the phase of the emission from A ahead of that from source B by 90°. The distance rA from A to a detector is greater than the corresponding distance rB from B by 130 m. What is the magnitude of the phase difference at the detector?

Answers

Answer:

[tex]X=165 \textdegree[/tex]

Explanation:

From the question we are told that:

Wavelength [tex]\lambda =360m[/tex]

Angle [tex]\theta=90 \textdegree[/tex]

Distance variation [tex]d=130m[/tex]

Generally the equation for phase difference X is mathematically given by

 [tex]X=\theta+\frac{d}{\lambda}*100[/tex]

 [tex]X=90+\frac{150}{360}*100[/tex]

 [tex]X=165 \textdegree[/tex]

Therefore Phase difference X is given as

 [tex]X=165 \textdegree[/tex]

Conditional waves contain a crest, trough, wavelength, and amplitude
True or False?​

Answers

Answer:

True

Explanation:

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

sino ang legendary hacker ng pilipinas?​

Answers

Answer:

Onel de guzman now he's 44,the first world's computer virus has admitted to his guilt.

(●’◡’●)ノ (ᗒᗣᗕ)՞ ༼ つ ◕◡◕ ༽つ

the path of the earth around the sun is called​

Answers

Answer:

Orbit.

Explanation:

An orbit is a regular, repeating path that one object in space takes around another one, it's an imaginary path of the Earth around the Sun.

A ray of light traveling in water hits a glass surface. The index of refraction of the water is 1.33, and that of the glass is 1.50. At what angle with the plane of the surface must the incident ray strike the glass in order that the polarization of the reflected ray is the greatest

Answers

Answer:

[tex]\mu=41.5\textdegree[/tex]

Explanation:

From the question we are told that:

Water index of refraction [tex]i_w=1.33[/tex]

Glass index of refraction [tex]i_g=1.50[/tex]

Generally the equation for Brewster's law is mathematically given by

 [tex]\theta=tan^{-1}(\frac{i_g}{i_w})[/tex]

 [tex]\theta=tan^{-1}(\frac{1.50}{1.33})[/tex]

 [tex]\theta=48.44 \textdegree[/tex]

Therefore Angle of incident to plane  \mu (normal at 90 degree to the surface)

 [tex]\mu=90\textdegree-\theta[/tex]

 [tex]\mu=90\textdegree-48.44\textdegree[/tex]

 [tex]\mu=41.5\textdegree[/tex]

Students have 4 different pairs of sunglasses, each with lenses where the polarization filter is oriented in different directions (indicated by the direction of lines drawn on the lenses below). They are planning to ride rafts down a river on a sunny day where there is lots of glare on the water. Which pair would they want to wear to eliminate the glare from the sun

Answers

Answer:

the lens you must select has an angle of 143º measured with respect to the horizontal, this angle is 53º with respect to the vertical.

Explanation:

The glare is caused by the reflection of light in the water, the polarization of the reflected light is polarized in a direction parallel to the surface of the water, the polarization is total for the angles

         n = tan  [tex]\theta_{p}[/tex]

         \theta_{p} = tan⁻¹ n

the refractive index for seawater is 1.33

         \theta_{p}= tan⁻¹  1.33

         \theta_{p} = 53º

for this angle the light is totally polarized, for the other angles the polarization is partial.

Based on this, the lenses must eliminate this polarization, so its polarization direction must have 90º with respect to this polarization,

          \theta_{lens} = 53 +90

           \theta_{lens}= 143º

Therefore, the lens you must select has an angle of 143º measured with respect to the horizontal, this angle is 53º with respect to the vertical.

A lens that could work is one that is polarized 45º with respect to the vertical.

The glass that is worn to eliminate glare must be able to remove glare away from the user.

What are sunglasses?

The term sunglasses refers to the kind of glasses that are worn to prevent glare from the sun. This is because the glasses are made of polaroid materials that eliminate glare.

The question is incomplete as the sunglasses are not shown. However, the glass that is worn to eliminate glare must be able to remove glare away from the user.

Learn more about sunglasses:https://brainly.com/question/23182689?

#SPJ5

Other Questions
Oscar has $30 from his allowance. There is a video game he wants to buy that costs $17.99, a chocolate bar that costs $0.79 and a remote control car that costs $8.99. I need help with this question PLZ HELP AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA A box of toy cars contains blue, orange, yellow, red, and blackcars. A separate box contains a male and a female actionfigure. What is the probability of randomly choosing an orangecar and a female action figure? Is it likely or unlikely that thiscombination is chosen? i will mark brain list and lots of points ne Pager Assignment for Little Bee excerpt by Chris CleaveYou are going to create a one-pager that demonstrates your understanding of the text.RequirementsUse one slide, one document page, one piece of paper, or a similar digital format for creating your one-pager.If you choose to create your document digitally, you can use images from the internet.If you choose to create your document using a piece of paper, you need to include color in your creation and will have to submit a clear picture of your one-pager.The title and author of the book needs to be included on your one-pagerYour one-pager needs to include at least THREE images that represent characters, the setting, or themes from the excerpt you read. These are pictures that you find on the internet or create on your own. Your one-pager needs to include TWO important quotations from the excerpt.Your one-pager needs to include TWO questions with answers to demonstrate your deep understanding of the text. (Think about literary devices used, motivations of characters, etc.)Your one-pager needs to include a prediction about what you think the rest of the book is about How does this Communist Red Guard quote reflect the political repression that Maos political opponents faced during the Cultural Revolution? "...Mao Tse-tung's thought is our lifeline. Those who oppose Mao Tse-tung's thought, no matter when they do so and what kind of authorities they are, will be publicly declared as evil by the entire Party and the whole nation." What is the volume of a sphere with a diameter of 49.3 cm, rounded to the nearesttenth of a cubic centimeter? Selena's dog completed an obstacle course that was 452 meters long. There were four parts to the course, all equal length. How long was each part of the course? A measure of the disorder of a system is called A vessel contained N2, Ar, He, and Ne. The total pressure in the vessel was 1100 torr. The partial pressures of nitrogen, argon, and helium were 110, 250, and 400 torr, respectively. The partial pressure of neon in the vessel was __________ torr. A) 420 B) 340 C) 200 D) 280 E) 760 The diameter of a dime is 17.91 millimeters, an the height is 1.35 millimeters. What is the volume of a dime? What is the volume of an oblique cylinder formed by stacking 50 dimes? Round your answers to the nearest hundredth. WILL GIVE BRAINLY WITHIN 3-5 MINUTES OF ANSWER; pls explain the Berlin Crisis in simple-people terms. Then find the values of x and y? find the distance between each pair of points. Round your answer to the nearest 10th if necessary Guess the song:I know that you're calling meTo light up and let the shadowThat follows you underneathI know that you're calling meI don't wanna play it safe'Cause I don't get down like thatJust keep falling into meI know I got your backAre you lonelyAre you lonelyAre you lonelyI'll stand by youI'll stand by youAre you lonelyAre you lonelyAre you lonelyI'll stand by youI'll stand by youWho ever said it was easyThey never know or doOh when these walls fall downI'll stand by youWhat you believe inI'll give it to you'Cause when these walls fall downI'll stand by youAre you lonelyAre you lonelyAre you lonelyI'll stand by youI'll stand by youAre you lonelyAre you lonelyAre you lonelyI'll stand by youI'll stand by you What time does the clock show?Please help I didnt get to learn this. Angle LMN and angle NMR are supplementary angles. What is the value of x in the diagram below? Arelli is 12 5 6 years old. Carl is 1 1 3 years younger than Arelli and Jane is 1 1 4 years younger than Carl. How old is Jane? What does the photograph show that the passage does not describe? A. The photograph shows the different colored rocks of the canyon. B. The photograph shows trees and shrubs that provide shade. C. The photograph shows how the sun hits the crevices of the rock formations. D. The photograph shows the rock formations that make the canyon special. what was one result of the neolithic revolution