Một nười thả 420g chì ở nhiệt độ 100°C và 260g nước ở nhiệt độ 58°C làm cho nước nóng lên tới 60°C . Cho nhiệt dung riêng của nước là 4200J/kg.K và bảo qua sự hao phí nhiệt ra môi trường bên ngoài . Hãy tính :

a) Nhiệt độ của chì khi có cân bằng nhiệt

b) Nhiệt lượng nước đã thu vào

c) Nhiệt dung riêng của chì

d) Nếu muốn nước và chì nóng tới nhiệt độ 75°C thì cần thêm vào một lượng chì ở nhiệt độ 150°C là bao nhiêu ?

Answers

Answer 1
hey what language is this?

Related Questions

In a given chemical reaction the energy of the products is less than the energy of the reactants which statement is true for this chemical reaction

Answers

Group of answer choices.

A. Energy is absorbed in the reaction.

B. Energy is released in the reaction.

C. There is no transfer of energy in the reaction.

D. Energy is lost in the reaction.

Answer:

B. Energy is released in the reaction.

Explanation:

A chemical reaction can be defined as a chemical process which typically involves the transformation or rearrangement of the atomic, ionic or molecular structure of an element through the breakdown and formation of chemical bonds to produce a new compound or substance.

Basically, there are two (2) main types of chemical reaction and these include;

I. Endothermic reaction: it's a chemical reaction in which heat is absorbed

II. Exothermic reaction: it's a chemical reaction in which heat is liberated into the environment.

In Chemistry, all chemical equation must follow or be in accordance with the Law of Conservation of Mass, which states that mass can neither be created nor destroyed by either a physical transformation or a chemical reaction but transformed from one form to another in an isolated (closed) system.

Generally, energy is released in a chemical reaction when the energy of the products is less than the energy of the reactants and it is referred to as an exothermic reaction.

However, when the energy of the products is greater than the energy of the reactants, energy is absorbed and it is referred to as an endothermic reaction.

What is an essential characteristic of an object in equilibrium?
1) zero velocity
2) zero acceleration
3) zero potential energy
4) zero kinetic energy

Answers

Answer:

2) zero acceleration

Explanation:

Motion can be defined as a change in the location (position) of a physical object or body with respect to a reference point.

This ultimately implies that, motion would occur as a result of a change in location (position) of an object with respect to a reference point or frame of reference i.e where it was standing before the effect of an external force.

Mathematically, the motion of an object is described in terms of time, distance, speed, velocity, position, displacement, acceleration, etc.

In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.

Generally, an object is said to be in equilibrium when neither the energy possessed by the object not state of motion changes with respect to time. Thus, the vector sum of all the forces acting upon an object that's in equilibrium is zero.

In conclusion, an essential characteristic of an object in equilibrium is zero (0) acceleration because there's no change in its velocity with respect to time.

Your new motorcycle weighs 2450 N.
What is
its mass in kilograms?


i understand the answer is 250kg because mass times gravity thing but why isn’t the answer negative cause gravity pulls down so wouldn’t be Negative answer not a positive answer

i was taught FW is always negative why isn’t it negative here

Answers

Answer:

Explanation:

The negative only matters reallly if you are dealing with a 2d system. I could even define down as positive and up as negative. However, usually you are taught that down is negative. It really doesn't matter because a force is a force. It is only given a direction relative to another force or vector direction.

What is physical measurement? in Science​

Answers

Answer:

physical measurement comprises the measurement of objects, things, etc. and is concerned with the measurement of height, weight, length, size, volume etc.

Q 2 A large circular field has a track along its inner boundary for conducting long distance sports events. The diameter XY of the track is 1 km. The following events were conducted.(use √ = 3.14 for calculations)

Event A- Fast walking along the diameter of the field.
Event B- A 15.7 km running race along the circular track.
Event C- A 25.12 km cycling race along the circular track.
(a) If the athletes walked from X to Y then, distance and displacement covered in Event A were
(i) Both 1.57km (ii) Both 1 km (iii) 1km and 1.57km respectively (iv) 1.57km and 1 km respectively.
(b)No of rounds required to complete Event B are
(i) 10 (ii) 2.5 (iii) 5 (iv)0.5
(c)If Pihu ran at an average speed of 3.14 km/h during Event B, then she would finish the race in
(i) 0.5hours (ii) 50mins (iii)500minutes (iv) 5 hours
(d) What should the average speed of cyclist Yousef be, so that he can complete Event C in 4hours?
(i) 6.28km/h (ii) 0.628km/h (iii) 12.56km/h (iv) 1.256km/h

Answers

Answer:

Explanation:

(a)

In event A , one has to walk along diameter of the field from X to Y.

In this event , walk is along a straight line , both displacement and distance covered will be same.

Distance = displacement = 1 km.

option ii is correct .

(b )

radius of circular track r = 0.5 km

length of track = circumference = 2π r

= 2 x 3.14 x .5 = 3.14 km

Length of running in event B is 15.7 km

No of rounds = 15.7 / 3.14 = 5

option iii is correct .

( c )

speed = length of race / time

time = length of race / speed

= 15. 7 km / 3.14 km /h

= 5 hours .

option iv is correct option.

(d)

In event C , length of race is 25.12 km

speed = length of race / time taken

= 25.12 km  / 4 hour

= 6.28 km/h .

Option i is correct.

Answer:

(a) (ii)

(b) (iv)

(c) (i)

(d) (i)

Explanation:

diameter, XY = 1 km

Event A- Fast walking along the diameter of the field.

Event B- A 15.7 km running race along the circular track.

Event C- A 25.12 km cycling race along the circular track.

(a) When athletes walked from X to Y , the distance is equal to the displacement which is equal to the diameter = 1 km.  

Option (ii).

(b) distance = 15.7 km

distance traveled by one round = 3.14 x 1 = 3.14 km

So, the number of round complete in B = 1.57/3.14 = 0.5

option (iv).

(c)If Pihu ran at an average speed of 3.14 km/h during Event B, then she would finish the race in

time, t = 1.57/3.14 = 0.5 hours

option (i)

(d) What should the average speed of cyclist Yousef be, so that he can complete Event C in 4hours?

Distance = 25.12 km

time , t = 4 hours

Speed = 25.12 / 4 = 6.28 km/h

Option (i)

Longitudinal waves are produced by

Answers

A longitudinal wave can be created in a slinky if the slinky is stretched out in a horizontal direction and the first coils of the slinky are vibrated horizontally. In such a case, each individual coil of the medium is set into vibrational motion in directions parallel to the direction that the energy is transported.

Hope it helped :))

Making rough estimates of physical quantities is usefulA. So that you can see if the answer to a problem makes physical sense.B. Because we only use approximate numbers in problems.C. Because the laws we use are not exact, so using exact numbers is not crucial.D.So that you can compute answers doing simpler math.

Answers

Answer:

A. So that you can see if the answer to a problem makes physical sense.

Explanation:

Science can be defined as a branch of intellectual and practical study which systematically observe a body of fact in relation to the structure and behavior of non-living and living organisms (animals, plants and humans) in the natural world through experiments.

An experiment can be defined as an investigation which typically involves the process of manipulating an independent variable (the cause) in order to be able to determine or measure the dependent variable (the effect).

This ultimately implies that, an experiment can be used by scientists to show or demonstrate how a condition causes or gives rise to another i.e cause and effect, influence, behavior, etc in a sample.

Measurements refers to the process which typically involves the process of identifying and determining the dimensions of a physical object. The dimensions include important parameters such as width, height, length, area, volume, circumference etc.

In Science, making rough estimates of physical quantities is useful so that you can see if the answer to a problem makes physical sense.

For example, you could make a rough estimate of a storage tank and deductively determine whether or not it's in tandem with its physical size in reality.

When a ray enters into air from glass slab
a) its wavelength decreases
b) it's wavelength increases
c) it's frequency increases
d) it's frequency decreases​

Answers

Answer:

a ) Its wavelength decreases

Explanation:

When a ray enters into air from glass slab its wavelength decreases.

I have possess'd your grace of what I purpose:And by our holy Sabbath have I swornTo have the due and forfeit of my bond.If you deny it, let the danger lightUpon your charter and your city's freedom !You'll ask me, why I rather choose to haveA weight of carrion flesh than to receiveThree thousand ducats : I'll not answer that:But, say, it is my humour(1) Whom are these lines addressed to? What is the context in which theselines are spoken?(ii) What has Shylock sworn on oath ?​

Answers

Answer:

1. These lines are addressed to Duke.

2. These lines show that Shylock is not willing to forgive the debt a merchant owes him, nor is he willing to justify why he demands that debt be paid, even if it seems cruel.

3. He swore by the Holy Sabbath, which is a holy day for him, who is a Jew. He swore he would get the debt money or a piece of the debtor's flesh.

Explanation:

The lines shown in the question above refer to "The Merchant of Venice" written by Shakespeare. In this story we are introduced to Antonio, a commercial who is very prejudiced against Jews, but when he needs money, he borrows from another merchant, Shylock, who is Jewish. Shylock agrees to lend money to Antonio, but determines the date that this money must be returned, in addition, Shylock states that he will lend the money if Antonio agrees that if this money is not paid by the specified date, Antonio will have to pay with half a kilo of flesh from his own body. Antonio agrees, but doesn't pay the money so Shylock goes after the flesh of Antonio's body and Duke tries to intervene because he thinks this is too cruel. At this point, Shylock speaks the lines shown in the question above, showing that he is not willing to change his mind.

Write a hypothesis about the use of an object’s physical characteristics to determine its density. Use the format "if . . . then . . . because . . .” and be sure to answer the lesson question "How can the density of an object be determined?”

Answers

Answer:

If 2 objects have the same mass, then which object has a larger volume will have a smaller density

Explanation:

Because density is the object's mass divided by volume

health ,population and environment education is for the enrichment of quality of life,justify the statement​

Answers

Answer:

hey !! here is a short and sweet answer to your question

=quality of life is directly determined by health ,education ,and life expectacy

=health Is a type of thing that gives employment to the person working in firm

hope u understand

Explanation:

que aceleración adquiere un cuerpo de 0.5 kg cuando actúa una fuerza n2​

Answers

La aceleración que adquiere el cuerpo de 0.5Kg es:

My second question for today :
Why do we ever have a blood moon?? What's the science behind it​

Answers

Answer:

vhijko and eye rudiieidjdjddjjd

Explanation:

jdjdjdjdjfjofkd ruudoeksowkosksd and nkdeondjvndkxnfuvjfk

If a lawn mower is pushed with a distance of 30 meters and 12N-m of work is exerted, calculate the force.

Answers

Answer:

Explanation:

W = FΔx so filling in:

12 = F(30) so

F = .4N

Answer the question based on this waveform.

A wave has a velocity of 24 m/s and a period of 3.0 s.


Choose the correct amplitude.

1/2 m
1/72 m
3 m
Cannot be determined from the given information

Answers

Answer:

Cannot be determined from the given information

Explanation:

Given the following data;

Velocity = 24 m/s

Period = 3 seconds

To find the amplitude of the wave;

Mathematically, the amplitude of a wave is given by the formula;

x = Asin(ωt + ϕ)

Where;

x is displacement of the wave measured in meters.

A is the amplitude.

ω is the angular frequency measured in rad/s.

t is the time period measured in seconds.

ϕ is the phase angle.

Hence, the information provided in this exercise isn't sufficient to find the amplitude of the waveform.

However, the given parameters can be used to calculate the frequency and wavelength of the wave.

A 0.080-kg egg test dummy is fitted with a helmet and attached to a swing. This egg test dummy is pulled back and released, allowing it to collide with a cement block. The impulse on the egg test dummy is - 0.39N.s is over an interval of 0.050 s. What is the magnitude of the force on the egg test dummy during this time interval?

Answers

Answer:

7.8 N

Explanation:

Applying,

I = Ft................. Eqaution 1

Where I = Impulse on the egg test dummy, F = Force on the egg test dummy during the time interval, t = time interval

make F the subject of the equation

F = I/t.................. Equation 2

From the question,

Given: T = -0.39 N.s, t = 0.050 s

Substitute these vales into equation 2

F = -0.39/0.050

F = -7.8 N

Hence the force that act on the egg test dummy is 7.8 N

A student increased the resister of the voltmeter year not the circuit

Answers

Answer:

Say the full question I can't understand what it is

Si la experiencia de Torricelli se llevara a cabo al nivel del mar usando un aceite de 890
kg/m3
de densidad en lugar de mercurio, ¿cuál sería la altura que alcanzaría la columna de
aceite?

Answers

Answer:

La columna de aceite tendría una altura de 11,613 metros.

Explanation:

El modelo de Torricelli basa el cálculo de la presión atmosférica mediante el concepto de presión hidrostática, en donde la densidad del fluido ([tex]\rho[/tex]), en kilogramos por metro cúbico, es inversamente proporcional a la altura de la columna ([tex]h[/tex]), en metros, para una igual presión atmosférica ([tex]P[/tex]), en atmósferas. Entonces, podemos estimar la altura de la columna mediante el siguiente modelo:

[tex]\rho_{Hg}\cdot h_{Hg} = \rho_{o}\cdot h_{o}[/tex] (1)

Donde:

[tex]\rho_{Hg}[/tex] - Densidad del mercurio.

[tex]h_{Hg}[/tex] - Altura de la columna de mercurio.

[tex]\rho_{o}[/tex] - Densidad del aceite.

[tex]h_{o}[/tex] - Altura de la columna del aceite.

Si sabemos que [tex]\rho_{Hg} = 13600\,\frac{kg}{m^{3}}[/tex], [tex]h_{Hg} = 0,760\,m[/tex] y [tex]\rho_{o} = 890\,\frac{kg}{m^{3}}[/tex], entonces la altura de la columna del aceite es:

[tex]h_{o} = \left(\frac{\rho_{Hg}}{rho_{o}} \right)\cdot h_{Hg}[/tex]

[tex]h_{o} = \frac{13600\,\frac{kg}{m^{3}} }{890\,\frac{kg}{m^{3}} }\times (0,760\,m)[/tex]

[tex]h_{o} = 11,613\,m[/tex]

La columna de aceite tendría una altura de 11,613 metros.

Impulse can be defined as

The frequency at which something occurs

The change in velocity

The change in momentum from an force within the system

The change in momentum from a force outside of the system

Answers

Explanation:

The change in momentum from an force within the system.

I think its D. The change in momentum from a force outside of the system

If Cl− is the only anion in the solution, what is the Cl− concentration in milliequivalents per liter?

Answers

Answer:

155mEq/L Cl-

Explanation:

A Ringer’s solution contains the following concentrations of cations: 146 mEq/L of Na+, 5 mEq/L of K+, and 4 mEq/L of Ca2+.

As Cl- is the only counterion of those cations:

For Na, the molecule is NaCl and the mEq/L of Cl- = mEq of Na+. The Cl- of the first ion is 146mEq/L Cl-

For K+, The molecule is KCl, mEq Cl- = 5mEq/L Cl-

And, for Ca2+, The molecule is CaCl2 but the equivalents of Ca2+ = Equivalents of Cl- = 4mEq/L Cl-

The total concentration of Cl- are:

146 + 5 + 4 =

155mEq/L Cl-

Can the magnitude of a vector ever (a) be equal to one of its components, or (b) be less than one of its components? 9. Can a particle with constant speed be accelerating? What if it has constant velocity? ​

Answers

Answer:

a) the other components are zero, in the direction of one of the coordinate axes

b) the magnitude is less than the value of one of its components, it must occur when the vector is in some arbitrary direction

9) constant velocity the acceleration must necessarily be zero,

constant speed  can be accelerated since it may be changing the direction of the velocity vector

Explanation:

Vectors are quantities that have modulo (scalar) direction and sense.

a)  If in a vector its magnitude is equal to one d its components implies that the other components are zero, therefore the vector must be in the direction of one of the coordinate axes

b) if the magnitude is less than the value of one of its components, it must occur when the vector is in some arbitrary direction, other than the direction of the axes, that is

          R² = x² + y²

where R is the magnitude of the vector e x, and are the components

9) When a particle has a constant velocity, the acceleration must necessarily be zero,

         v = vo + a t

The bold letters indicate vectors If a = 0 implies that v = vo

If a particle has constant speed it can be accelerated since it may be changing the direction of the velocity vector, this type of acceleration has the name of centripetal acceleration

Which of the following provides the best evidence in support of the big bang
theory?
O A. The way a balloon expands
B. The confirmation of special relativity
C. The uniformity of cosmic background radiation
D. The separation of energy levels in an atom

Answers

C. The Uniformity of Cosmic Background Radiation

Hai vận động viên chạy trên cùng 1 đoạn đường, vận động
viên A chạy với vận tốc 12 m/s vận động viên B chạy với vận tốc 36
km/h. Hỏi vận động viên nào chạy nhanh hơn?

Answers

Answer:

Pemain A

Explanation:

Mengingat data berikut;

Kecepatan pemain A = 12 m/s

Kecepatan pemain B = 36 km/h

Untuk menentukan siapa pelari tercepat di antara dua pemain;

Pertama-tama, kita harus mengubah kecepatan menjadi satuan standar pengukuran yang sama.

Jadi, mari kita gunakan pengukuran umum meter per detik.

Konversi:

36 km/h = (36 * 1000)/(60 * 60)

36 km/h = 36000/3600

36 km/h = 10 m/s

Kecepatan pemain B = 10 m/s

Oleh karena itu, dibandingkan dengan kecepatan pemain A; pemain A lebih cepat.

The answer is D. I can't figure out why? The human range is from 20 Hz to 20 kHz...

Answers

Answer:

(C) 2 kHz

Explanation:

The normal hearing frequency range of a person has a minimum of about 20 Hz, which is the about the frequency of the lowest pipe organ pipe. The maximum frequency that a human can ear comfortably is 20 kHz

Therefore, the student will not be able to hear sounds less than 20 Hz, and sounds above 20 kHz and the student will only be able to hear the 2 kHz sound.

research paper on tsunamis (4-5 paragraphs minimum) 3) Tsunamis how they work….evacuation routes, structures built in oceans to protect, early detection, etc

Expectations:

A. Must be at least 4 full paragraphs. (probably will need to be more)

B. Must have an introductory paragraph that explains what the problem is, and the general overview of the paper.

C. Must Define Problem, including details and how it relates to Irvine

D. Main Body of Paper (probably couple of paragraphs) This is where you will show what you found out in your research. Make sure to include things like current use/techniques, as well as what technological advancements are being researched to improve your specific topic/issue.

E. Conclusion: Short summary of main points. Your Opinion on what is working and why (or what is not working and why)

F. Citations: Must use at LEAST 3 sources. Must site works at end, in either MLA or APA format, AND must site them where used in the paper (also MLA or APA format).

Make sure all work is yours and original. Copying is cheating. Using information from a source without citing is plagiarism.

Answers

A must be at least 4 full paragraphs probably will need more

If we go on the top of the Mountain we will our weight increase or decrease?​

Answers

Answer:

increase

Explanation:

guesshejwoowsnnsnakalalapqjhdjd

Answer:

our weight would decrease.

Explanation:

because of you burning all those calories and fat from hiking up the mountain.

Does anyone know the answer ? I forgot my calculator.


12 x sin50

Answers

12 × sin50 = 9.192533317........

Give a general description of how winds form

Answers

Answer:

Wind comes from pressure and temperature differences.

Explanation:

Have you ever opened a window on a hot day to let a breeze in? What is happening is a rush of air to balance out temperatures. This goal for uniformity is why ice melts in a glass of warm coffee and air rushes out of a balloon.

Answer:

Wind forms when the sun heats one part of the atmosphere differently than another part. This causes expansion of warmer air, making less pressure where it is warm than where it is cooler. Air always moves from high pressure to lower pressure, and this movement of air is wind.

Explanation:

Raquel establece que la rapidez del sonido en el aire en un día es de 346 m/s . Días después hace la misma medición obteniendo una rapidez de 340 m/ s . ¿Cuál será la temperatura del aire en cada día?

Answers

Answer:

La ecuación para la velodiad del sonido en aire esta dada por:

[tex]v = \sqrt{ \frac{\gamma*R*T}{M} }[/tex]

Resolviendo esto para T, obtenemos:

[tex]T = v^2*(\frac{M}{\gamma*R} )[/tex]

donde:

T = temperatura del aire en grados Kelvin

γ = constante adiabatica = 1.4

R = constante del gas ideal =

M = masa molar del aire = 29*10^(-3) kg/mol

Si sabemos que el primer día la velocidad es 346 m/s, tenemos:

v = 346 m/s

Ahora podemos reemplazar todos esos valores en la ecuación para T, y asi obtener:

[tex]T = (346m/s)^2*(\frac{29*10^{-3}kg/mol}{1.4* 8.31 J/mol*K} ) = 298.42 K[/tex]

Para el segundo día la velocidad es 340 m/s, entonces ese día la temperatura va a ser:

[tex]T = (340m/s)^2*(\frac{29*10^{-3}kg/mol}{1.4* 8.31 J/mol*K} ) = 288.16 K[/tex]

The acidity model given by pH = -log10[H+] where acidity (pH) is a measure of the hydrogen ion concentration [H+] (measured in moles of hydrogen per liter) of a solution. Using this model, determine the pH of a solution with a hydrogen ion concentration of 2.3 X 10^-5 (round your answer to the nearest hundredth)

Answers

Answer:

Hydrogen ion concentration, [H+] :

[tex]{ \bf{[H {}^{ + } ] = 2.3 \times {10}^{ - 5} \: mol \: l {}^{ - 1} }}[/tex]

Substitute to the negative logarithmic model:

[tex] = { \tt{ - log(2.3 \times {10}^{ - 5} ) }} \\ pH = 4.64[/tex]

Other Questions
CName the painting displayed above. Describe its artistic characteristics and the subject matter.Mark this and retumSave and ExitNenSubmit Explain the difference between macro-sociology and micro-sociology. Identify one macro-level theory and one micro-level theory. Explain how each theory views society. Who was responsible for establishing the League of Nations, an organization that would settle disagreements betweennations? Marion is a great manager and he has a number of special skills. In particular, Marion has the ability to get his subordinates to do more than would be normally expected. Which of the following terms best describes Marion?a. Transactional leaderb. Supportive leaderc. Charismatic leaderd. People-oriented leader Your customer calls you in the morning and tells you to lock the interest rate at the 5.5% you initially disclosed. You commit to lock the rate, but your day becomes busy and you aren't able to lock it until later in the day. When you go to lock the rate, you notice that the pricing has changed since this morning and the rate of 5.5% is now going to cost an additional $500.00. What is the most appropriate course of action? A 0.40-kg mass attached to the end of a string swings in a vertical circle having a radius of 1.8 m. At an instant when the string makes an angle of 40 degrees below the horizontal, the speed of the mass is 5.0 m/s. What is the magnitude of the tension in the string at this instant Which of the following is a solution to 2sin2x+sinx-1=0? Based on the excerpt, the conclusion that personal mood seems to affect honesty" is best supported by which of thefollowing statements?O Relaxing summer and fall holidays generally cause payment rates to drop.O Stressful fall and winter holidays generally cause payment rates to drop.O Relaxing summer and fall holidays generally cause theft rates to increase.Stressful fall and winter holidays generally cause theft rates to remain steady. a. The amount of each lease payment will be increased by the option price. b. The lessee must decrease the present value of the lease payments by the present value of the option price. c. There is no impact as the option does not enter into the transaction until the end of the lease term. d. The lessee must increase the present value of the lease payments by the present value of the option price. how do you correct series in a sentence Building A is 170 feet shorter than building B. The total height of the two building is 1490 feet. Find the height of each building. Which of the following scatterplots would have a trend line with a negative slope? please give me truth answer1) who is ja Na ?2) who love oh ja Na ??? IdiomsSalad Days what does that mean binod said tome,"you have done your work.( change into indirect speech) which of the following are affected by environmental factor1) Housing 2) Folk tales 3) Traditional religions4) Cuisine A) 1, 2B) 1, 3C) 1, 2, 3D) 1, 2, 3, 4 PLEASE HELPPPPPPPPPPP Divide 5x^2+3x-2 by x + 1 a period of one thousand years The parts of the economy necessary for creating a particular good or serviceare the:A. cost-benefit analysis.O O OB. factors of production.C. division of labor.D. production possibilities.