When should the shop ventilation fan be turned on?

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.

Simple

You are working at taco bell, so hypothetically, you would be reconsidering your life choices while driving god who knows how many beans

Answer:

the answer is B ;)

Explanation:

Answer:

technical engineering

The different branches of engineering involved in manufacturing a general-purpose elevator are:

1. Mechanical engineering

2. Electrical engineering

3. Civil engineering

4. Industrial engineering

5. Safety engineering

The different branches of engineering involved in manufacturing a general-purpose elevator are:

1. Mechanical engineering: Responsible for the design, construction, and operation of the elevator's mechanical systems.

2. Electrical engineering:  Responsible for the design, installation, and maintenance of the elevator's electrical systems.

3. Civil engineering: Responsible for the design and construction of the elevator's shaftway and hoistway. T

4. Industrial engineering: Responsible for the efficient design and operation of the elevator's manufacturing process.

5. Safety engineering: Responsible for ensuring that the elevator is safe to operate.

Learn more about elevators on:

https://brainly.com/question/30490732

#SPJ2

Answer:

Ford Raptor

Explanation:

Answer:

you can't spell Btw but anyways i this its any type of jeep  

Explanation:

At constant temperature, the volume of a confined gas is inversely proportional to the pressure to which it is subjected.

At constant pressure, the volume of a confined gas is directly proportional to the absolute temperature.

A change in pressure at an point in an enclosed fluid at rest is transmitted undiminished to all points in the fluid.

When 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]

At a constant temperature, the gas volume is inversely proportional to the pressure applied

[tex]\tt P_1.V_1=P_2.V_2[/tex]

The 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]

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

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

.

Answer:

2 8/10TH INCHES

Explanation:

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

Answer: 2.125 in.

Explanation:

Answer:

2 1/8 in is the answer

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:

Answer:

the answer should be 16

Answer:

A. PMC tends to fit the construction purposes for which it was specifically designed.

Explanation:

took the test go it right

Answer:

its about 2 and a half

Explanation:

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

Answer:

cadmuim

Explanation:

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.

Answer:

18.

Explanation:

well take 7 away from 29 that leaves you with 22 half of 22 is 11 and if the were 7 more boys than girls you would add the 11 and 7 that makes 18 boys and 11 girls in the class