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3 years ago

In a real machine, the work output is always less than the work input. a. True b. False

1 answer:

4 0

<span>In a real machine, the work output is always less than the work input is true. The answer is letter A. it follows the law of entropy where no energy can be converted completely into work. Under this law, Carnot’s theorem states that Carnot’s engine can perform 100% of work. However, no such engine has ever succeeded the conversion of work into 100%. The greatest efficiency so far is at 80%. Because there will always be factors that could affect the conversion of work. </span>

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Un objeto de 1 kg se mueve con una velocidad cambia 10m/s¿se ha realizado trabajo sobre el objeto?

Wewaii [24]

Answer:

I don't speak spanish oso sorry

Explanation:

6 0

3 years ago

a tms (transcranial magnetic stimulation) device creates very rapidly changing magnetic fields. the field near a typical pulsed-

Digiron [165]

Part A : 4.33 Volt.

Part B : 4764 Amperes.

Given Data :

Field near a typical pulsed-field machine rises from 0 T to 2.5 T in 200 μs.

Axis of his 2.1-cm-diameter wedding band is parallel to the field.

Part A :

induced emf = rate of change of magnetic flux

= d (B A )/dt

= A dB/dt

= { π (2.1 x 10^-2 / 2)^2) (2.5) } / (200 x 10^-6)

E = 4.33 Volt

Part B :

R = rho L / A

R = { (6.2 x 10^-8) ( π x 0.021) } / (4.5 x 10^-6)

R = 9.10 x 10^-4 Ohm

We know, (I = V/ R)

I = 4.33 Volts / 9.10 x 10^-4 Ohm

I = 4764 Amperes

What exactly is the function of TMS?

Transcranial magnetic stimulation (TMS) is a noninvasive procedure that uses magnetic fields to stimulate nerve cells in the brain to alleviate depression symptoms. TMS is usually used when other depression treatments have failed.

Find more on TMS at : brainly.com/question/13851741

#SPJ4

➤ Although your question isn't complete, I may have assumed that you were referring to this specific question.

The complete question is :

A TMS (transcranial magnetic stimulation) device creates very rapidly changing magnetic fields. The field near a typical pulsed-field machine rises from 0 T to 2.5 T in 200 μs. Suppose a technician holds his hand near the device so that the axis of his 2.1-cm-diameter wedding band is parallel to the field.

Part A: What emf is induced in the ring as the field changes? Express your answer to two significant figure E= ___ unit_

Part B: If the band is made of a gold alloy with resistivity 6.2×10−8Ω⋅m and has a cross-section area 4.5 mm2 , what is the induced current? Express your answer to two significant figures and include the appropriate units. I= ___ units__

6 0

1 year ago

An object of volume 0.0882 m3 is

vfiekz [6]

The density of the fluid is 776.3 $m^{-3}$

<u>Explanation:</u>

Buoyant force is the upward pushing force whenever an object is trying to get immersed in fluid. So this is the force given by the fluid on the object which is trying to get immersed. The buoyant force is found to be directly proportional to the product of density of the object, volume of the object. And here the acceleration due to gravity will be acting as proportionality constant.

$Buoyant force = Density \times Volume \times Acceleration$

As, buoyant force is given as 671 N and volume is 0.0882 $m^{3}$ and acceleration is known as 9.8 m/ $s^{2}$ . Then density is

$\text { Density }=\frac{\text { Buoyant force }}{\text {Volume } \times \text {Acceleration}}$

Thus,

$\text { Density }=\frac{671}{0.0882 \times 9.8}=\frac{671}{0.86436}=776.296 \mathrm{kg} / \mathrm{m}^{3}$

Density is 776.3 kg $m^{-3}$ .

7 0

3 years ago

What would be the coefficient of performance if the refrigerator (operating between the same temperatures) was instead used as a

viktelen [127]

Complete Question

A certain refrigerator, operating between temperatures of -8.00°C and +23.2°C, can be approximated as a Carnot refrigerator.

What is the refrigerator's coefficient of performance? COP

(b) What If? What would be the coefficient of performance if the refrigerator (operating between the same temperatures) was instead used as a heat pump? COP

Answer:

$COP = 8.49$

$COP_1 = 9.49$

Explanation:

From the question we are told that

The lower operation temperature of refrigerator is $T_1 = -8.00^oC = 265 \ K$

The upper operation temperature of the refrigerator is $T_2 = 23.2 ^oC = 296.2 \ K$

Generally the refrigerators coefficient of performance is mathematically represented as

$COP = \frac{T_1}{T_2 - T_1 }$

=> $COP = \frac{265}{296.2 - 265 }$

=> $COP = 8.49$

Generally if a refrigerator (operating between the same temperatures) was instead used as a heat pump , the coefficient of performance is mathematically represented as

$COP_1 = \frac{T_2}{ T_2 - T_1}$