Answer:
We need 154.737 grams of water at 5 ºC to obtain a final temperature of 43 ºC.
Explanation:
From Thermodynamics we know that mixing processes involve the interaction of substance at different temperatures so that thermal equilibrium is reached by cooling down the substance with highest temperature and heating up the subtance with lowest temperature.
Let suppose that mixing occurs at steady state, that is, that system does not have energy interactions with surroundings. According to the First Law of Thermodynamics, we get that energy interactions are represented by:
[tex]H_{L} + H_{H} -H_{R} = 0[/tex]
[tex]H_{L} + H_{H} = H_{R}[/tex] (Eq. 1)
Where:
[tex]H_{L}[/tex] - Enthalpy of cold water, measured in joules.
[tex]H_{H}[/tex] - Enthalpy of hot water, measured in joules.
[tex]H_{R}[/tex] - Enthalpy of mixed water, measured in joules.
Since there are no phase changes, we can expand formula by using the definition of sensible heat. That is:
[tex]m_{L}\cdot c_{w}\cdot T_{L}+m_{H}\cdot c_{w}\cdot T_{H} = m_{R}\cdot c_{w}\cdot T_{R}[/tex]
[tex]m_{L}\cdot T_{L}+m_{H}\cdot T_{H} = m_{R}\cdot T_{R}[/tex] (Eq. 2)
Where:
[tex]m_{L}[/tex], [tex]m_{H}[/tex], [tex]m_{R}[/tex] - Masses of cold, hot and mixed water, measured in grams.
[tex]c_{w}[/tex] - Specific heat of water, measured in joules per gram-Celsius.
[tex]T_{L}[/tex], [tex]T_{H}[/tex], [tex]T_{R}[/tex] - Temperatures of cold, hot and mixed water, measured in Celsius.
But we know from Principle of Mass Conservation that:
[tex]m_{R} = m_{L}+m_{H}[/tex] (Eq. 3)
Then, we simplify (Eq. 2) and clear the mass of cold water:
[tex]m_{L}\cdot T_{L}+m_{H}\cdot T_{H} = (m_{L}+m_{H})\cdot T_{R}[/tex]
[tex]m_{H}\cdot (T_{H}-T_{R}) = m_{L}\cdot (T_{R}-T_{L})[/tex]
[tex]m_{L} = m_{H}\cdot \left(\frac{T_{H}-T_{R}}{T_{R}-T_{L}} \right)[/tex] (Eq. 4)
If we know that [tex]m_{H} = 140\,g[/tex], [tex]T_{L} = 5\,^{\circ}C[/tex], [tex]T_{R} = 43\,^{\circ}C[/tex] and [tex]T_{H} = 85\,^{\circ}C[/tex], the mass of cold water needed to obtain a final temperature is:
[tex]m_{L} = (140\,g)\cdot \left(\frac{85\,^{\circ}C-43\,^{\circ}C}{43\,^{\circ}C-5\,^{\circ}C} \right)[/tex]
[tex]m_{L} = 154.737\,g[/tex]
We need 154.737 grams of water at 5 ºC to obtain a final temperature of 43 ºC.
A bicycle has tires that are 26 inches in diameter. The while in motion, the tires rotate through 125 complete revolutions. How fast has the bicycle traveled? Give the answer in feet
Answer:
850.8480103 feet
Explanation:
First you take the diameter and find the circumference, which is (2)(pi)(r) plug in your r which is 26/2= 13 so 2(13)(pi) and multiply taht by 125 after that take your answer and divide by 12which is 850.8480103
Ilove you is an example of?
Answer:
the brain has diffrent parts so one of them has a connect to the heart so when you fall in love the brain is signaling the heart poison and that posion tells the heart i you react about it and its a example of your heart
What are the causes of kickback on a table-saw?
and
How should a saw be used to prevent kick-back from occurring?
What is the relationship between permanent modular construction (PMC) and purpose-built construction?
O PMC tends to fit the construction purposes for which it was specifically designed
O PMC is designed to be customizable and adaptable in the field.
O PMC tends to be best suited to large construction projects encompassing a variety of purposes.
O PMC is adaptable to a broad range of construction purposes.
Answer:
A. PMC tends to fit the construction purposes for which it was specifically designed.
Explanation:
took the test go it right
How should you set up your notes when using the Cornell method?
0 with pictures and maps
0 with levels and sublevels
0 with right and left sides
0 with tables and charts
Answer:
With right and left side charts
Explanation:
I was doing research on this exact question, so here is what I have been looking at;
The Cornell method uses a two-column approach. The left column takes up no more than a third of the page and is often referred to as the “cue” or “recall” column. The right column (about two-thirds of the page) is used for taking notes using any of the methods described above or a combination of them. After class or completing the reading, review your notes and write the key ideas and concepts or questions in the left column. You may also include a summary box at the bottom of the page, in which to write a summary of the class or reading in your own words.
Answer:
with right and left sides
Explanation:
PLEASE HELP! ASAP!!!!
Lyndon is investigating whether putting plastic on her windows will help seal out cold winter drafts. She covers a window on the south side of her house with plastic and measures the inside temperature near the window. She also measures the inside temperature near a window without plastic on the north side of her house. The windows are the same size and design. Why is this not an ideal controlled investigation?
A.
The windows should be different sizes to introduce variation.
B.
The drafts at each window may be different because the windows aren’t near each other.
C.
Temperature isn’t a good indicator of cold winter drafts.
D.
Outside temperature is a better indicator of cold winter drafts than inside temperature.
E.
The type of plastic used in the investigation isn’t mentioned.
2. If a paint contains
then the palnt booth filter must be considered hazardous waste.
A) O Lead
B) O Cadmium
C) O Chromium
D) O All of the above
Answer:
cadmuim
Explanation:
Reducing waste in a shop doesn't help eliminate safety hazards for
employees.
A True
B. False
Pleasseeee help
Answer:
False
Explanation:
Waste in the shop such as garbage, can cause air pollution, which causes various respiratory diseases and other adverse health effects on employees, as contaminants are inhaled and absorbed from lungs into other parts of the body.
These toxic substances in air contaminated by waste that are inhaled by employees include carbon dioxide, nitrous oxide and methane.
Thus, reducing waste which constitutes toxic substances helps to eliminate safety hazards for employees.
Answer:
Explanation:
F
what is the best off rode car I think jeep wrangler
Answer:
Ford Raptor
Explanation:
Answer:
you can't spell Btw but anyways i this its any type of jeep
Explanation:
How are angular cuts made on a horizontal bandsaw
Group of answer choices
Turning the blade guides to the desired angel
Angular cuts cannot be made on this saw
Holding the workpiece higher on one end than the other
Swiveling the vise to the desired angel
Answer:
A. Turning the blade guides to the desired angel
Explanation:
In a horizontal bandsaw, the user moves the blade to sweep an arc from a fixed cutting plane that will produced repeated number of fixed angle cuts.
Using horizontal bandsaw, only straight cuts at a fixed angle can be attained.
Fixed angle cuts can be made from a horizontal bandsaw thus answer choice B is incorrect.
While using the horizontal bandsaw, the work piece is held stationary while the blade slides on the rollers. Thus answer choice C is incorrect.
The material is normally held with claps to a stationary position before a cut is made by the blade that that repeatedly attains cuts at fixed angle. The vise is not involved. Answer choice D is incorrect.
Match each context to the type of the law that is most suitable for it.
Boyle’s Law
Charles’ Law
Pascal’s Law
(Match them to the context it goes to)
At constant temperature, the volume of a confined gas is inversely proportional to the pressure to which it is subjected.
A change in pressure at an point in an enclosed fluid at rest is transmitted un diminished to all points in the fluid.
At constant pressure, the volume of a confined gas is directly proportional to the absolute temperature.
At constant temperature, the volume of a confined gas is inversely proportional to the pressure to which it is subjected.
Charles’ LawAt constant pressure, the volume of a confined gas is directly proportional to the absolute temperature.
Pascal’s LawA change in pressure at an point in an enclosed fluid at rest is transmitted undiminished to all points in the fluid.
Further explanationCharles’ LawWhen the gas pressure is kept constant, the gas volume is proportional to the temperature
[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]
Boyle’s LawAt a constant temperature, the gas volume is inversely proportional to the pressure applied
[tex]\tt P_1.V_1=P_2.V_2[/tex]
Pascal’s LawThe pressure exerted by the liquid in a closed space is continued in all directions equally
[tex]\tt P_1=P_2\\\\\dfrac{F_1}{A_1}=\dfrac{F_2}{A_2}[/tex]
I really don't understand this please help!!!
Answer:
2 8/10TH INCHES
Explanation:
Dr. Ronny wants to measure small distances. Which device should he use?
A.
altimeter
B.
laser micrometer
C.
piezoelectric gauge
D.
thermometer
E.
dialyzer
Answer:
the answer is B ;)
Explanation:
what happens if you put too many beans in a car and then drive it?
Simple
You are working at taco bell, so hypothetically, you would be reconsidering your life choices while driving god who knows how many beans
I can't figure this out
Answer: 2.125 in.
Explanation:
Answer:
2 1/8 in is the answer
Architects have identified the two most important knowledge areas for their profession as design and mathematics.
True
False
Answer:
False
Explanation:
The two most important fields of expertise for their career were not defined as architecture and mathematics by architects.
It offers expertise and expertise to architects and engineers that can not be gained by practicing alone.
answer:
the answer is false
.
When should the shop ventilation fan be turned on?
Answer:
When cars are running
Explanation:
The shop ventilation fan should be turned on when there are smells, dampness, smoke, and other contaminants in the shop environment. Also, when there is excessive temperature and moisture it should be turned on.
What is Ventilation?
Ventilation assists in cooling your attic by pushing away suffocating hot air from within and bringing in cool air from outside. This keeps hot air from entering your home and raises the temperature in your living area, reducing the strain on your air conditioner.
Exhaust fans purify the air by eliminating smells, dampness, smoke, and other contaminants. Also, it avoids Mold that may grow when there is steam and moisture in the air.
Hence, The shop ventilation fan should be turned on when there are smells, dampness, smoke, and other contaminants in the shop environment. Also, when there is excessive temperature and moisture it should be turned on.
Learn more about Ventilation here:
https://brainly.com/question/11471552
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