What are Teets<br><br> I am so confused right kn

An inventor claims to have invented a heat engine that operates between the temperatures of 627°C and 27°C with a thermal effici

Oksana_A [137]

Answer Explanation:

the efficiency of the the engine is given by=1- $\frac{T_2}{T_1}$

where T₂= lower temperature

T₁= Higher temperature

we have given efficiency =70%

lower temperature T₂=27°C=273+27=300K

higher temperature T₁=627°C=273+627=900K

efficiency=1- $\frac{T_2}{T_1}$

=1- $\frac{300}{900}$

=1-0.3333

=0.6666

=66%

66% is less than 70% so so inventor claim is wrong

3 0

3 years ago

Why do we need technical sketching?

Scrat [10]

Technical Drawings give a better understanding of what is needed and required in the project.

Explanation:

8 0

3 years ago

Read 2 more answers

Shortly after the introduction of a new coin, newspapers published articles claiming the coin is biased. The stories were based

garik1379 [7]

Answer:

(a) 0.12924

(b) Taking into consideration significance level of 0.05 yet the value of p is greater than 0.05, it suggests that the coin is fair hence the coin can be used at the beginning of any sport event.

Explanation:

(a)

n=200 for fair coin getting head, p= 0.5

Expectation = np =200*0.5=100

Variance = np(1 - p) = 100(1-0.5)=100*0.5=50

Standard deviation, $s = \sqrt {variance}=\sqrt {50}= 7.071068$

Z value for 108, $z =\frac {108-100}{7.071068}= 1.131371$

P( x ≥108) = P( z >1.13)= 0.12924

(b)

Taking into consideration significance level of 0.05 yet the value of p is greater than 0.05, it suggests that the coin is fair hence the coin can be used at the beginning of any sport event.

3 0

3 years ago

6. What types of injuries can occur in an electronics lab and how can they be prevented?

marysya [2.9K]

Answer:

The most common injuries in a chemistry lab is making a fire, heat burns, chemical burns, cuts and scrapes, contamination, inhalation, and spills and breaks.

1.) You can prevent making a fire by making sure you close and seal flammable materials.

2.) You can prevent heat burns by teaching the students how to properly use tongs,water baths, and other cooling equipment.

3.) You can prevent chemical burns by treating the chemicals with caution, measure carefully, and use the approved containers.

4.) You can prevent cuts and scrapes by telling the students how to use the blades safely, and also when they are disposing broken or sharp items they should know how to wrap them up so no one else will get hurt.

5.) You can prevent contamination by washing your hands, protect their clothing and skin with a lab coat or a lab apron, gloves and glasses, and cleaning your area where the germs of the chemicals were so no one will become.

6.) You can prevent inhalation by opening up windows, using ventilation fans, and using an equipment that measures the amount of gas emission in a room.

7.) Finally, you can prevent spills and breaks by telling the students what will happen if anything spills, and tell them to clean up.

8 0

3 years ago

A two-dimensional flow field described by

Oduvanchick [21]

Answer:

the answer is

Explanation:

<h2> We now focus on purely two-dimensional flows, in which the velocity takes the form </h2><h2>u(x, y, t) = u(x, y, t)i + v(x, y, t)j. (2.1) </h2><h2>With the velocity given by (2.1), the vorticity takes the form </h2><h2>ω = ∇ × u = </h2><h2> </h2><h2>∂v </h2><h2>∂x − </h2><h2>∂u </h2><h2>∂y </h2><h2>k. (2.2) </h2><h2>We assume throughout that the flow is irrotational, i.e. that ∇ × u ≡ 0 and hence </h2><h2>∂v </h2><h2>∂x − </h2><h2>∂u </h2><h2>∂y = 0. (2.3) </h2><h2>We have already shown in Section 1 that this condition implies the existence of a velocity </h2><h2>potential φ such that u ≡ ∇φ, that is </h2><h2>u = </h2><h2>∂φ </h2><h2>∂x, v = </h2><h2>∂φ </h2><h2>∂y . (2.4) </h2><h2>We also recall the definition of φ as </h2><h2>φ(x, y, t) = φ0(t) + Z x </h2><h2>0 </h2><h2>u · dx = φ0(t) + Z x </h2><h2>0 </h2><h2>(u dx + v dy), (2.5) </h2><h2>where the scalar function φ0(t) is arbitrary, and the value of φ(x, y, t) is independent </h2><h2>of the integration path chosen to join the origin 0 to the point x = (x, y). This fact is </h2><h2>even easier to establish when we restrict our attention to two dimensions. If we consider </h2><h2>two alternative paths, whose union forms a simple closed contour C in the (x, y)-plane, </h2><h2>Green’s Theorem implies that </h2><h2> </h2><h2> </h2><h2> </h2><h2> </h2><h2> </h2><h2></h2><h2></h2>

5 0

3 years ago

What are Teets I am so confused right kn