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3 years ago

A heat engine is a device able to transform work into heat. a. True b. False

Engineering

1 answer:

mojhsa [17]3 years ago

3 0

Answer:

Option B: False

Explanation:

A heat engine is a device which operates in a manner that heat is converted into mechanical work.

A simple example of a heat engine is a drinking bird. The oscillatory motion of the drinking bird is as a result of the thermal expansion and contraction of a chemical compound in its beak, which creates an imbalance in its position of equilibrium. This causes it to oscillate.

Heat engines usually work by extracting heat once there is a temperature gradient available in the system and using it to perform work. Another good example is the internal combustion engine. It extracts heat from the explosion of the burning fuels and uses it to power the car.

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Technician A says that the connecting rod and main bearing caps should be marked before removing to ensure that they can be inst

Rama09 [41]

Answer:

Technician A

Explanation:

This is because when the dimacations are made, the surface area and length respectively can be maintained to reduce to idea of force which may lead to damage

3 0

2 years ago

In a tensile test on a steel specimen, true strain = 0.12 at a stress of 250 MPa. When true stress = 350 MPa, true strain = 0.26

scZoUnD [109]

Answer:

The strength coefficient is $625$ and the strain-hardening exponent is $0.435$

Explanation:

Given the true strain is 0.12 at 250 MPa stress.

Also, at 350 MPa the strain is 0.26.

We need to find $(K)$ and the $(n)$ .

$\sigma =K\epsilon^n$

We will plug the values in the formula.

$250=K\times (0.12)^n\\350=K\times (0.26)^n$

We will solve these equation.

$K=\frac{250}{(0.12)^n}$ plug this value in $350=K\times (0.26)^n$

$350=\frac{250}{(0.12)^n}\times (0.26)^n\\ \\\frac{350}{250}=\frac{(0.26)^n}{(0.12)^n}\\ \\1.4=(2.17)^n$

Taking a natural log both sides we get.

$ln(1.4)=ln(2.17)^n\\ln(1.4)=n\times ln(2.17)\\n=\frac{ln(1.4)}{ln(2.17)}\\ n=0.435$

Now, we will find value of $K$

$K=\frac{250}{(0.12)^n}$

$K=\frac{250}{(0.12)^{0.435}}\\ \\K=\frac{250}{0.40}\\\\K=625$

So, the strength coefficient is $625$ and the strain-hardening exponent is $0.435$ .

5 0

3 years ago

Explain biometric senser.

Contact [7]

Biometric sensors are used to collect measurable biological characteristics from a human being, which can then be used in conjunction with biometric recognition algorithms to perform automated person identification.

8 0

3 years ago

Read 2 more answers

What were some of the challenges to safety resulting from such radical airframe designs as highly swept wings, high wing loading

Andrew [12]

How to take off and land, stopping considerations (stopping distance), control system capability over a large speed range and flutter, and structural integrity for the wing platform and speed range.

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3 years ago

A sprinter reaches his maximum speed in 2.5sec from rest with constant acceleration. He then maintains that speed and finishes t

liubo4ka [24]

The maximum Speed of the Sprinter from the velocity time graph of his motion is; 11.98 m/s

<h3>How to find the maximum speed?</h3>

We are given;

Initial Speed; u = 2.5 s

Total distance; d = 100 m

Total time; T = 9.6 s

The total distance is;

d = ¹/₂(9.6 + (9.6 - 2.5) * v

where v is maximum speed.

Thus;

¹/₂(9.6 + (9.6 - 2.5) * v = 100

16.7v = 200

v = 200/16.7

v = 11.98 m/s

Read more about Maximum Speed at; brainly.com/question/4931057

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3 0

2 years ago