A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25°C by absorbing heat from geothermal water that enters the evaporator at 500C at a rate of 0.065 kg/s and leaves at 40°C. The refrigerant enters the evaporator at 20°C with a quality of 23 percent and leaves at the inlet pressure as saturated vapor. The refrigerant loses 300 W of heat to the surroundings as it flows through the compressor and the refrigerant leaves the compressor at 1.4 MPa at the same entropy as the inlet. Determine: (a) The degrees of subcooling of the refrigerant in the condenser, b)-The mass flow rate of the refrigerant . (c) The heating load and the COP of the pump, and d)-The theoretical minimum power input to the compressor for the same heating load.

Answer:

Answer is c Heisenberg's uncertainty principle

Explanation:

According to Heisenberg's uncertainty principle there is always an inherent uncertainty in measuring the position and momentum of a particle simultaneously.

Mathematically

[tex]\Delta x\times \Delta \overrightarrow{p}\geq \frac{h}{4\pi }[/tex]

here 'h' is planck's constant

Answer:

Process 1:W=0

Process 2:W= -386.13 KJ  

Process 3:W= -468 KJ

Explanation:

Process 1:[tex]P_1=1 bar,V_1=2.6m^3[/tex]

Process 2:[tex]P_2=2.7bar,V_2=2.6m^3[/tex]

Process 3:[tex]V_3=1.5 m^3[/tex]

       [tex]V_4=0.5 m^3[/tex]

Process 1:

    Work (W)=0  ,because it is constant volume process.

Process 2:

It is constant temperature process so PV=C

[tex]P_2V_2=P_3V_3[/tex]

[tex]P_3=\dfrac{P_2V_2}{V_3}[/tex]

[tex]P_3=\dfrac{2.7\times 2.6}{1.5}[/tex]

[tex]P_3=4.68 [/tex]bar

So work in constant  temperature process

W=[tex]P_2V_2\ ln\dfrac{V_3}{V_2}[/tex]

W=[tex]270\times 2.6\ ln\dfrac{1.5}{2.6}[/tex]    (1 bar=100KPa)

W= -386.13 KJ  

Negative sign means it is compression process.

Process 3:

It is a constant pressure.

So work W=[tex]P_3(V_4-V_3)[/tex]

W=468(0.5-1.5) KJ

W= -468 KJ

Negative sign means it is compression process.

Answer:

A substitutional solid solution is a kind of alloying process used to improve or strengthen a purer metal by alloying it. this process works out by adding atoms of an alloy element to the atoms of the crystal lattice of the parent or base element, thus forming a substitutional solid solution. This process generates local non uniformity in the lattice due to the presence or mixing of an alloy element with the base element which impedes the plastic deformation.

Factors that favor the formation of substitutional solid solution are:

Answer:

Substitutional solids solution are formed when there is change in position of atom named as A in lattice by some other atoms of different atoms named as B.

Explanation:

Substitutional solids solution are formed when there is change in position of atom named as A in lattice by some other atoms of different atoms named as B.

Strengthening of this solution occurs when solute atom is lager than solvent atom so that it can replace its position

factor affect the extent of solid solution is

1) Relative atomic size

2) crystal structure

3) chemical affinity

4) valency

Answer:

Out of the four options provided

option A. actuator

is correct

Explanation:

An actuator is the only device out of the four mentioned devices that provides power and ensures the motion in it in order to manipulate the movement of the moving parts of the damper or a valve used whereas others like ratio regulator are used to regulate air or gas ratio and none mof the 3 remaining options serves the purpose

Answer: (d)Rotational speed of the shaft

Explanation: Shaft design is the design of a shaft that is used for defining the stresses at certain critical part of shaft. The shaft design has shaft diameter as a major part and this is determined by several factors like type of bearing , deflection, torque,safety factor etc.

But the least important factor for determining of the  diameter is the rotational speed because it defines the rotation of an object  around a particular axis, where is it states about the number of turns divisible by time. Therefore option(d) is the correct option.

Answer:

option a is correct answer i.e. d = 1.6 mm

Explanation:

From conservation principle

force by jet = force required to hold the jet

force by the jet is written as

[tex]force  = \dot{m}(v_{1}-v_{2})\[/tex]

force required to hold the jet = 8N

[tex]\dot{m}(v_{1})\ = 8[/tex]

[tex]\dot{m}=0.13 kg/s[/tex]

[tex]v_{1} = 61.58 m/s[/tex]

we know that mass flow rate is given as

[tex]\dot{m}=\rho Av_{1}[/tex]

substituting value to get required  diameter of the nozzle

[tex]0.13=1000*\frac{\pi }{4}d^{2}*61.58[/tex]

d = 1.6 mm

If water is boiling at 130 degrees Celsius inside a pressure cooker, the pressure is approximately 2.7 atmospheres

To determine the pressure inside a pressure cooker where water is boiling at 130 degrees Celsius, we use the properties of water and its boiling point at various pressures.

For water, the pressure at which the boiling point is elevated to 130 degrees Celsius can be found using steam tables.

At 130 degrees Celsius, the saturation pressure of water is approximately 2.7 atmospheres (atm). This is equivalent to :

= 2.7 x 101.325 kPa

= 273.5775 kPa, or about 2.7 bar (since 1 bar = 100 kPa)

Answer: False

Explanation: Horizontal-axis wind turbine is the major part of wind industry. Horizontal axis have rotating axis of wind turbine in horizontal direction.Horizontal wind produces more electricity from a particular amount of wind that is provided and thus is preferred more.

vertical-axis wind turbines have the rotational axis of the turbine in vertical or perpendicular direction and have easy installation even where wind conditions are not predictable and is lighter in weight but are not able to produce the large amount of electricity as compared to horizontal-axis wind turbine.

Thus the statement given is false.

Answer: B) Increased strength and increased toughness

Explanation: Short fibre reinforcement has the major property of being tough and has high strength. Short fibre reinforcement is basically a process of addition of the short fibre to the thermoplastic materials to make the improvement in their quality and working by increasing their strength.They also have application in many areas because of their hardness property as well as being cost -effective. Thus, the option (b) is the correct option.

Answer:

a)True

Explanation:

According to Fourier's law,It states that Heat transfer is directly proportionate to the temperature gradient.For unidirectional conduction

    [tex]q''\alpha\dfrac{dT}{dx}[/tex]

Where q'' is the heat flux.

When This directly proportionate is remove then one constant will on that place and that constant is called conductivity of material.

  [tex]q''=K\dfrac{dT}{dx}[/tex]

So total heat transfer Q

      [tex]Q=KA\dfrac{dT}{dx}[/tex]

When conductivity (K) of material is not constant

K=[tex]K_0[/tex](a+bT)  where a,b are constant.

So from the above expression we can say that heat transfer in material will depend on temperature difference,material property and on on geometry of object.

True.

An intrinsic semiconductor is a pure semiconductor. At room temperature it behaves as an insulator because it only has a few free and hollow electrons due to thermal energy.

In an intrinsic semiconductor there are also electron fluxes and gaps, although the total current resulting is zero. This is because the action of thermal energy produces free electrons and gaps in pairs, so there are as many free electrons as there are gaps with which the total current is zero.

Answer: b) possible and currently inexpensive as compared to wind turbines.

Explanation: Wind harvesting through kites is a process that will require less expenses in making and maintenance of it .Kites can be termed as the wind generator that is unconventional. The set up for the kite wind generator is also easy to install and also less costly as compared with turbines. So the correct option is option(a) .

Answer:

Mass does not affect oscillation frequency.                                                    

Explanation:

Let the bob of the pendulum makes a small angular displacement θ. When the pendulum is displaced from the equilibrium position, a restoring force tries to act upon it and it tries to bring the pendulum back to its equilibrium position. Let this restoring force be F.

Therefore, F = -mgsinθ  

Now for pendulum, for small angle of θ,

sinθ[tex]\simeq[/tex]θ

Therefore, F = -mgθ

Now from Newton's 2nd law of motion,

F = m.a = -mgθ

[tex]\Rightarrow m.\frac{d^{2}x}{dt^{2}} = - mg\Theta[/tex]

Now since, x = θ.L

[tex]\Rightarrow L.\frac{d^{2}\Theta }{dt^{2}}= -g\Theta[/tex]

[tex]\Rightarrow \frac{d^{2}\Theta }{dt^{2}}= -\frac{g}{L}.\Theta[/tex]

[tex]\Rightarrow \frac{d^{2}\Theta }{dt^{2}}+\frac{g}{L}.\Theta =0[/tex]

Therefore, angular frequency

 [tex]\omega ^{2}[/tex] = [tex]\frac{g}{L}[/tex]

ω = [tex]\sqrt{\frac{g}{L}}[/tex]

Also we know angular frequency is , ω = 2.π.f

where f is frequency

Therefore

2πf = [tex]\sqrt{\frac{g}{L}}[/tex]

f = [tex]\frac{1}{2 \pi }\sqrt{\frac{g}{L}}[/tex]

So from here we can see that frequency,f is independent of mass, hence it does not affect frequency.

Answer:

c) 1440 W

Explanation:

P = V*i = (12A)*(120V) = 1440W

According to the scenario, the amount of power that is dissipated by the heater is 1440 W. Thus, the correct option for this question is C.

Power may be defined as the amount of energy that is significantly transferred or converted per unit of time. The unit of power is the watt (W). It may be typically calculated with the help of the given formula:

According to the context of this question, the amount of power that is dissipated within the heater is calculated by the following formula:

Therefore, according to the scenario, the amount of power that is dissipated by the heater is 1440 W. Thus, the correct option for this question is C.

To learn more about Power, refer to the link:

https://brainly.com/question/1634438

#SPJ5

Answer:

Explained below

Explanation:

Beats are interference pattern between two sounds of slightly different frequencies perceived as periodic vibration in volume whose rate is difference of the two.

Both octave and decibel are the terms of measurement.

Octave(In electronics) is a logarithmic unit for ratio between frequencies,with one octave corresponding to doubling of frequency. For example frequency one octave is from 40 Hz to 80 Hz.

Whereas decibel is a unit of sound intensity. It is one-tenth of A bel. In electronics it is used measure power level of an electrical signal by comparing it with given level of logarithmic scale.

Answer:

1. High friction

2. High extrusion temperature

Explanation:

Surface cracking on extruded products are defects or breakage on the surface of the extruded parts. Such cracks are inter granular.

           Surface cracking defects arises from very high work piece temperature that develops cracks on the surface of the work piece. Surface cracking appears when the extrusion speed is very high, that results in high strain rates and generates heat.

          Other factors include very high friction that contributes to surface cracking an d chilling of the surface of high temperature billets.

Answer:

b).the kinematic viscosity is absolute viscosity divided by mass density

Explanation:

Viscosity is a fluid property that offers resistance or obstruction to deformation or fluid flow.

Viscosity is of two types--

1. Absolute viscosity , μ

2. Kinematic viscosity, ν

Absolute viscosity :

Absolute viscosity is also called the dynamic viscosity. It is the internal resistance of the fluid to flow.

Kinematic viscosity :

Kinematic viscosity is the ratio of dynamic viscosity to the density of the fluid.

Absolute viscosity measures a fluid's internal friction, while kinematic viscosity is the ratio of absolute viscosity to the fluid's density. Viscosity affects how easily a liquid flows; higher intermolecular forces lead to higher viscosity, and this property is critical in fluid dynamics studies.

The difference between absolute viscosity and kinematic viscosity is that absolute viscosity, often referred to simply as viscosity, represents the fluid's resistance to flow and is a measure of the internal friction within the fluid. Kinematic viscosity, on the other hand, takes the fluid's density into account and is the ratio of the fluid's absolute viscosity to its density. While absolute viscosity is measured in units like Pascal-seconds (Pa·s), kinematic viscosity is measured in square meters per second (m²/s).

Viscosity is influenced by intermolecular forces; liquids that can flow easily, such as ethanol, have lower viscosities, while substances like motor oil with higher intermolecular forces have higher viscosities. Measuring the time it takes for steel balls to fall through a fluid or for a fluid to flow through a narrow tube helps determine the fluid's viscosity. In other words, absolute viscosity is concerned with the sheer strength and flow resistance of a fluid, while kinematic viscosity relates to the movement of the fluid under the force of gravity considering its volume.

Answer:

The Biot number for this sphere is  0.03

Explanation:

Given data in equation

diameter (d) = 60 mm = 60/1000 = 0.06 m

heat transfer coefficient (h)  = 10 w/m²-K

thermal conductivity (K) = 20 W/m-K

To find out

Biot number for sphere

Solution

we will find boit number by this given formula

Biot Number = ( h × S ) / K     ..................1

here h and K value is given in question

and S = diameter/2

S= 60/2 = 30 mm = 0.03 m

Now put these value S, h and K in equation 1

Biot Number = ( 10 × 0.03 ) / 10

Biot Number =  0.03

Answer:

It is True that in a quasi static process,  the system remains infinitesimally close to equilibrium state throughout the process.

Explanation:

The literal meaning of the word "quasi" is 'almost' and static is 'rest', so quasi static state means almost at rest state of the system

It can be further explained as the process, in thermodynamics which allows the system to be carried to slowly to maintain its equilibrium or to remain in its internal equilibrium state. Such a process is known as quasi-static process. Such processes also allow all isothermal and adiabatic processes to operate slowly so as not to disturb their internal equilibrium. this makes the system to always remain in thermal equilibrium

Answer Explanation:

SPRING STIFFNESS :The stiffness of a body is a measure of resistance offered by an elastic body to deformation.it is denoted by K every object has some stiffness for spring the spring stiffness is the force required to cause unit deflection

DAMPING CONSTANT: the damping constant is a number decided by manufacturer that describes the material property. Damping is an influence within an oscillatory system that has the effect of restricting its oscillation

GIVEN:

Amplitude, A = 0.1mm

Force, F =1 N

mass of motor, m = 120 kg

operating speed, N = 720 rpm

[tex]\frac{A}{F}[/tex] =  [tex]\frac{0.1\times 10^{-3}}{1} = 0.1\times 10^{-3}[/tex]

Formula Used:

[tex]A = \frac{F}{\sqrt{(K_{t} - m\omega ^{2}) +(\zeta \omega ^{2})}}[/tex]

Solution:

Let Stiffness be denoted by 'K' for each mounting, then for 4 mountings it is 4K

We know that:

[tex]\omega = \frac{2 \pi\times N}{60}[/tex]

so,

[tex]\omega = \frac{2 \pi\times 720}{60}[/tex] = 75.39 rad/s

Using the given formula:

Damping is negligible, so, [tex]\zeta = 0[/tex]

[tex]\frac{A}{F}[/tex] will give the tranfer function

Therefore,

[tex]\frac{A}{F}[/tex] = [tex] \frac{1}{\sqrt{(4K - 120\ ^{2})}}[/tex]

[tex]0.1\times 10^{-3}[/tex] =  [tex] \frac{1}{\sqrt{(4K - 120\ ^{2})}}[/tex]

Required stiffness coefficient, K = 173009 N/m = 173.01 N/mm

Answer:

c). surface pressure and depth

Explanation:

We know that fluid pressure is measured in two different ways namely --

1. Pressure measured above complete vacuum or absolute zero is called Absolute Pressure.

2.Pressure measured above atmospheric pressure is called Gauge Pressure.

In the figure below, we can find the pressure at the point A in the static fluid inside the tank which is at a depth of h from the water surface.

Let the atmospheric pressure which is acting on the water surface be [tex]P_{atm}[/tex].

Let ρ be the density of water and g be the acceleration due to gravity.

Therefore we know that pressure at a point in a fluid is

P = ρ[tex]\times[/tex]g[tex]\times[/tex]h

Therefore total pressure acting on the point A in a fluid is

[tex]P_{tot}[/tex] = [tex]P_{atm}[/tex] + P

[tex]P_{tot}[/tex] = [tex]P_{atm}[/tex] + ρ[tex]\times[/tex]g[tex]\times[/tex]h

Thus, pressure at a point A in a static fluid depends on the surface pressure and the depth of the point from the free surface.

Answer:

[tex](M_t)_{rated}=61.11lb-in[/tex]

Explanation:

speed of motor (N)=1500 rpm

power=4 hp = [tex]4 \times 0.7457 [/tex] =2.9828 KW

service factor(k)= 2.75

now,

[tex]KW=\frac{2\pi n M_t}{60 \times 10^6} \\2.9828=\frac{2\pi \times 1500 M_t}{60 \times 10^6}\\M_t=\frac{2.9828\times 60 \times 10^6}{2\pi \times 1500 }[/tex]

[tex]M_t= 18,989.09 \ N-mm= 168.06 lb-in[/tex]

torque rating

[tex](M_t)_{design}=k_s\times (M_t)_{rated}\\168.06= 2.75\times (M_t)_{rated}\\(M_t)_{rated}=\frac{168.06}{2.75} \\(M_t)_{rated}=61.11lb-in[/tex]

Answer:

So heat transfer is 696 kJ

Explanation:

Given:

K = 1.4

[tex]C_{v}[/tex] = 0.716 kJ/kg

[tex]C_{p}[/tex] = 1 kJ/kg

R = 0.287 kJ/kg

V = 1 [tex]m^{3}[/tex]

P = 1000 kPa

T = 1000 K

Work delivered, δW = 696 kJ

It is isothermal process, so the initial and final temperature are same, that is T₁ = T₂ and the internal energy is zero (dU =0)

Therefore from 1st law of thermodynamcis,

δQ = dU + δW

     = 0 + 696

     = 696 kJ

So heat transfer is 696 kJ

Answer:

mass density of fluid is = 1000*0.721 = 721 kg/m3

so option e is correct

11. option e is correct ( a and b).

Explanation:

given data

specific gravity of fluid  = 0.721

we know that mas density of water [tex]{\gamma _{water}}[/tex] is 1000 kg/m3

specific gravity of water is given as S.G

[tex]S.G = \frac{\gamma _{fluid} }{\gamma _{water}}[/tex]

mass density of fluid is = 1000*0.721 = 721 kg/m3

A fluid is combined form used for gas and liquid.

it offer negligible resistance to  stress (shear stress)

Answer:

121.20 cm

Explanation:

Given data in question

inner dia = 5 cm

flow rate = 75  umin = 1.25 ×10³ cm³/sec

Solution

First we calculate Re by this formula

Re= [tex]\frac{V × D}{v)}[/tex]  = [tex]\frac{Q × D}{π/4 × D²× v)}[/tex]

Re= [tex]\frac{4Q }{π × D× v)}[/tex]

here we know Q is flow rate and D is dia of pipe and v is kinematic viscosity that is 1.14 × [tex]10^{-2}[/tex] cm ² / sec

so Re= [tex]\frac{4Q }{π × D× v)}[/tex]

Re = [tex]\frac{4×1.25× 10³ }{π × 5 × 1.14 × 10^{-2}  )}[/tex]

So Re will be 27936 that is greater than 4000 thats why it is turbulent flow

and we know [tex]\frac{Length}{dia)}[/tex] ≡ 4.4 [tex]Re^{1/6}[/tex]

so [tex]\frac{Length}{dia)}[/tex] ≡ 24.24

length will be 121.20 cm

Answer:

answer is option A i.e.45.45 hp

Explanation:

Given data:

load =20000 ft lb/s

efficiency = 80%

we know that

1 hp = 550 ft lb/s

minimum horsepower rating can be obtained by using following formula

minimum horse power rating = [tex]\frac{load}{efficiency * 1 horse power} \\[/tex]

                                                = [tex]\frac{20000}{0.8*550} = 45.45 hp[/tex]

Answer: A

Explanation:

Microchips are made out of silicone witch is a polymer.

Answer:

its a

Explanation:

Answer:

1590 m^2

Explanation:

Given data in this question

Diameter = 45 m

power = 700 kW

wind speed = 12 m/s

turbine speed = 1500 rpm

To find out

swept area of the wind turbine

Solution

we know wind turbine is rotate circular form

and diameter is given so by the area of circular swept we will calculate it

we know area =  [tex]\pi /4[/tex] × d²

put the value of d here

area =  [tex]\pi /4[/tex] × 45²

swept area = 1590 m^2

Answer:

True.

Explanation:

According the engineering flow they don not possess flow energy when they are in rest.

When they are in motion they show a translation energy.

The features if fluids may be different according the variables of pressure and temperature.