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3 years ago

For a refrigerator, COP<1 a) True b) False

Engineering

1 answer:

WINSTONCH [101]3 years ago

4 0

Answer:

False

Explanation:

COP is Coeficient of performance, it relates useful heat moved with work consumed, it is used in refrigerators and heat pumps.

For refrigerators the useful heat is the one extracted from the cold reservoir. Therefore:

$COP = \frac{Tcold}{T.hot - Tcold}$

This often exceeds 1.

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Relation between Poisson's ration, young's modulus, shear modulus for an isotropic material

poizon [28]

Answer:

E=2 G(1+2μ)

Explanation:

Isotropic material :

Those material have same property in all direction is known as isotropic material.

Homogeneous material :

Those material have same property through out the volume is known as homogeneous material.

Relationship between Poisson ratio ,young modulus and shear modulus:

E=2 G(1+2μ)

Relationship between Poisson ratio ,bulk modulus and shear modulus:

E=2 K(1-μ)

Where

E is young modulus.

G is shear modulus.

μ is Poisson ratio.

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3 years ago

In order to give a gradual increase in section modulus, frame reinforcement plates must be:Group of answer choicesrectangular.cu

Nataliya [291]

Answer:

Technician A says that when fifth wheel brackets are bolted to frame rails, the section modulus over that section of the frame is increased.

Explanation:

hope i helped

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3 years ago

A series RLC circuit consists of a 100 W resistor, a 0.15 H inductor, and a 30 µF capacitor. It is attached to a 120 V/60 Hz pow

lisov135 [29]

Answer:

yeah basically

Explanation:

3 0

3 years ago

The pressure in an automobile tire depends on the temperature of the air in the tire. When the air temperature is 25°C, the pres

kirza4 [7]

Answer:

ΔP=19.76 KPa

$\Delta m=10^{-3}\ gm$

Explanation:

Given that

$T_1= 25C, P_1= 210 \KPa \gauge$

atmospheric pressure = 100 kPa.

So absolute pressure = Atmospheric pressure + gauge pressure

$P_1=210+100\ KPa$ (absolute)

$P_1=310\ KPa$ (absolute)

Here volume of air is constant .We know that for constant volume pressure

$\dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}$

here

$T_2= 44C$

$T_1=273+25=298K$

$T_2=273+44=317K$

$\dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}$

$\dfrac{310}{298}=\dfrac{P_2}{317}$

$P_2=329.76\ KPa$ (absolute)

So rise in pressure

$\Delta P=P_1-P_2$

ΔP=329.76-310 KPa

ΔP=19.76 KPa

$m_1=\dfrac{P_1V}{RT_1}$

$m_1=\dfrac{310\times 0.025}{0.287\times 298}$

$m_1=0.090615\ kg$

$m_2=\dfrac{P_2V}{RT_2}$

$m_2=\dfrac{329.76\times 0.025}{0.287\times 317}$

$m_2=0.090614\ kg$

Δm=0.090615 - 0.090614 kg

$\Delta m=10^{-3}\ gm$

4 0

3 years ago

What kind of abilities are needed to run a business

nordsb [41]

Answer:

Essential business skills:

1. Financial management. Being able to effectively manage your finances is critical. ...

2. Marketing, sales and customer service. ...

3. Communication and negotiation. ...

4. Leadership. ...

5. Project management and planning. ...

6. Delegation and time management. ...

7. Problem solving. ...

8. Networking.

8 0

2 years ago