A heat engine operating between a pair of hot and cold reservoirs with respective temperatures of 500 K and 200 K will have what maximum efficiency?
A) 60%
B) 50%
C) 40%
D) 30%

Answer:

a. True

Explanation:

When a p-type semiconductor is placed adjacent to an n-type semiconductor  the common plane thus formed is termed as P-N Junction or  P-N Junction Diode.

The diode is formed by melting both p-type and n-type semiconductors through a special manufacturing process called "Thermo-Compression Proces".

The P-N junction has a property of one-way conduction. It means it only allows the current to pass through it in one direction and the current flow is practically zero in the other direction. Thus, it can act as a diode. The p-side acts as the anode, while the n-side acts as the cathode.

Hence, the correct option is:

a. True

Answer:

hope u can understand the method

Answer:

J = 1600 kg-m/s

Explanation:

Given that,

The mass of charging bull rams, m = 800 kg

Initial speed, u = 5 m/s

Final speed, v = 3 m/s

We need to find the impulse the bull  experience by smashing the fence. Let it is J. We know that, impulse is equal to the change in momentum such that,

J = m(v-u)

Put all the values,

J = 800(3-5)

= 800(-2)

= -1600 kg-m/s

Hence, the magnitude of impulse is equal to 1600 kg-m/s.

Answer:

34.24 %

Explanation:

Since I₀ is the intensity of the un-polarized light, the intensity I₁ of the light polarized by the 1st sheet is (by the one-half rule) I₁ = I₀/2.

The intensity of polarized light I from a polarized source I' is I = I'cos²Ф where Ф is the angle between the direction of I' and I. Since the second sheet has its transmission axis at 25° with respect °o the 1st sheet, the intensity of light I₂ from the second sheet is I₂ = I₁cos²25°.

Also, the 3rd sheet has its transmission axis 47° with respect to the 1st sheet. So, the angle between the transmission axis of the 2nd sheet and 3rd sheet is 47° - 25° = 22°. So, the intensity I₃ from the 3rd sheet is I₃ = I₂cos²22°

Finally, the 4th sheet has its transmission axis 10° with respect to the 3rd sheet. So, the intensity I₄ from the 4th sheet is I₄ = I₃cos²10°.

So,  I₄ = I₃cos²10°

I₄ = I₂cos²22°cos²10°

I₄ = I₁cos²25°cos²22°cos²10°

I₄ = (I₀/2)cos²25°cos²22°cos²10°

I₄/I₀ = cos²25°cos²22°cos²10°/2

I₄/I₀ = (cos25°cos22°cos10°)²/2

I₄/I₀ = (0.9063 × 0.9272 × 0.9848)²/2

I₄/I₀ = 0.8275²/2

I₄/I₀ = 0.6848/2

I₄/I₀ = 0.3424

So, as a percentage,

I₄/I₀ × 100% = 0.3424 × 100% = 34.24 %

Answer:

a

because the mechanical wave is when it goes over and over again

Answer:

The answer is a like i said 3hrs ago i dont know if this guy copied me tbh

Explanation:

Answer:

Δx = 6.33 x 10⁻³ m = 6.33 mm

Explanation:

We can use the Young's Double Slit Experiment Formula here:

[tex]\Delta x = \frac{\lambda L}{d}\\\\[/tex]

where,

Δx = distance between consecutive dark fringes = width of central bright fringe = ?

λ = wavelength of light = 633 nm = 6.33 x 10⁻⁷ m

L = distance between screen and slit = 3.7 m

d = slit width = 0.37 mm = 3.7 x 10⁻⁴ m

Therefore,

[tex]\Delta x = \frac{(6.33\ x\ 10^{-7}\ m)(3.7\ m)}{3.7\ x \ 10^{-4}\ m}[/tex]

Δx = 6.33 x 10⁻³ m = 6.33 mm

Answer:

the magnitude of the magnetic field of the wave is 16.7 nT

Explanation:

Given the data in the question;

Electric field E = 5.00 V/m

we know that the expression for the electric field of an electromagnetic wave in terms if magnetic field is;

E = cB

where c is the speed of light ( 3 × 10⁸ m/s )

and B is the magnetic field

so we solve for the magnetic field

B = E / c

we substitute in the value of E and c

B = (5.00 V/m) / (3 × 10⁸ m/s)

B = 1.67 × 10⁻⁸ T

B = 1.67 × 10⁻⁸ T [tex]( \frac{1nT}{10^{-9}T} )[/tex]

B = 16.7 nT

Therefore, the magnitude of the magnetic field of the wave is 16.7 nT

Answer:

12558 J

Explanation:

Please do mark as brainliest. Hope this helps! :)

Answer:

B)   I₀ = I_f= 0, C) vₐ = [tex]\frac{m_w}{m_a} \ v_w[/tex] ,  D)      t = [tex]\frac{m_a}{m_w} \ \frac{L}{v_w}[/tex]

Explanation:

A) in the attachment you can see a diagram of the movement of the key and the astronaut that is in the opposite direction to each other.

B) Momentum equals the change in momentum in the system

          I = ∫ F dt = Δp

since the astronaut has not thrown the key, the force is zero, so the initial impulse is zero

           I₀ = 0

The final impulse of the two is still zero, since it is a vector quantity, subtracting the impulse of the two gives zero, since it is an isolated system

             I_f = 0

C) We define the system formed by the astronaut and the key, for which the forces during the separation are internal and the moment is conserved

initial instant.

         p₀ = 0

final instant

         p_f = [tex]m_a v_a - m_w v_w[/tex]

We used the subscript “a” for the astronaut and the subscript “w” for the key

the moment is preserved

        po = p_f

        0 = mₐ vₐ - m_w v_w

        vₐ = [tex]\frac{m_w}{m_a} \ v_w[/tex]

D) as the astronaut goes at constant speed we can use the uniform motion relationships

         vₐ = x / t

         t = x / vₐ  

         t = [tex]\frac{m_a}{m_w} \ \frac{L}{v_w}[/tex]

Answer:

Ohms

Explanation:

The unit of resistance is ohms.

Answer:

677 m

Explanation:

Using the definition of the sine of an angle, we can write

sin 14.1 = (height of mountain) / (slope length of mountain)

sin 14.1 = H / (2780 m) ---> H = (2780 m) x sin 14.1

= 677 m

The height of the mountain is 677.21 m

The given parameters;

length of the slope, L = 2780 m

angle of inclination, Ф = 14.1°

let the height of the mountain, = h

A simple sketch of the problem is given below;

                    ↓P

                    ↓

                    ↓ h

                    ↓                                            14.1°

                    ↓------------------------------------------------Q

A straight line  joining PQ  is  the hypotenuse of the right triangle.

The height of the right triangle is calculated as follows;

[tex]sin(14.1) = \frac{h}{PQ} \\\\\h = PQ \times sin(14.1)\\\\h = 2780 \times sin(14.1)\\\\h = 677.21 \ m[/tex]

Thus, the height of the mountain is 677.21 m

Learn more here: https://brainly.com/question/4326804

Answer:

Kinetic energy is energy possessed by a body by virtue of its movement. Potential energy is the energy possessed by a body by virtue of its position or state. While kinetic energy of an object is relative to the state of other objects in its environment, potential energy is completely independent of its environment. Hence the acceleration of an object is not evident in the movement of one object, where other objects in the same environment are also in motion. For example, a bullet whizzing past a person who is standing possesses kinetic energy, but the bullet has no kinetic energy with respect to a train moving alongside.

I think this answer is helped you

Answer:

the what state does alduos is 500 stack of ml tayo the little man ♂️ jajao

kalokoha ya

ansjsjdk

Answer:

the answer of this question is true

Answer:

B. evaluation

Explanation:

An employee can be defined as an individual who is employed by an employer of labor to perform specific tasks, duties or functions in an organization.

Basically, an employee is saddled with the responsibility of providing specific services to the organization or company where he is currently employed while being paid a certain amount of money hourly, daily, weekly, or monthly depending on the contractual agreement between the two parties (employer and employee).

Hence, while an employer may be the owner of a business firm or company, an employee is a subordinate employed to provide unwavering services to the employer while also, being professional and diligent at all times.

Human resources management (HRM) can be defined as an art of managing, controlling and improving the number of people (employees or workers), functions, evaluation of employees, activities which are being used effectively and efficiently by an organization.

Hence, human resources managers are saddled with the responsibility of recruiting, evaluating, managing and improving the welfare and working conditions of the employees working in an organization.

Basically, the human resources manager carry out appraisals on the performance of the various employees working in an organization. These informations about employees are typically used for promotional purposes, allowances and other benefits or form of rewards.

Answer: Liquid 2, if it's 3 g/mL and liquid 2 has 6gs and 2 mLs than it's 3g/mL

Answer:

(a) Energy Density = 160.94 J/m³

(b) Energy Stored = 0.192 J

Explanation:

(a)

The energy density of the magnetic field inside the solenoid is given by the following formula:

[tex]Energy\ Denisty = \frac{B^2}{2\mu_o}\\[/tex]

where,

B = magnetic field strength of solenoid = [tex]\frac{\mu_oNI}{l}[/tex]

Therefore,

[tex]Energy\ Density = \frac{\mu_oN^2I^2}{2l^2}[/tex]

where,

μ₀ = permeability of free space = 4π x 10⁻⁷ N/A²

N = No. of turns = 1300

I = current = 8.15 A

L = length = 66.2 cm = 0.662 m

Therefore,

[tex]Energy\ Density = \frac{(4\pi\ x\ 10^{-7}\ N/A^2)(1300)^2(8.15\ A)^2}{2(0.662\ m)^2}[/tex]

Energy Density = 160.94 J/m³

(b)

Energy Stored = (Energy Density)(Volume)

Energy Stored = (Energy Density)(Area)(L)

Energy Stored = (160.94 J/m³)(0.0018 m²)(0.662 m)

Energy Stored = 0.192 J

Answer:

you need 7 points and the other team just needs to stop you from scoring

Explanation:

Answer:

Hello! Your answer would be, A) True

Explanation:

Hope I helped! Ask me anything if you have any questions. Brainiest plz!♥ Hope you make a 100%. Have a nice morning! -Amelia♥

Answer:

Explanation:

Dear Student, this question is incomplete, and to attempt this question, we have attached the complete copy of the question in the image below. Please, Kindly refer to it when going through the solution to the question.

To objective is to find the:

(i) required heat exchanger area.

(ii) flow rate to be maintained in the evaporator.

Given that:

water temperature = 300 K

At a reasonable depth, the water is cold and its temperature = 280 K

The power output W = 2 MW

Efficiency [tex]\zeta[/tex] = 3%

where;

[tex]\zeta = \dfrac{W_{out}}{Q_{supplied }}[/tex]

[tex]Q_{supplied } = \dfrac{2}{0.03} \ MW[/tex]

[tex]Q_{supplied } = 66.66 \ MW[/tex]

However, from the evaporator, the heat transfer Q can be determined by using the formula:

Q = UA(L MTD)

where;

[tex]LMTD = \dfrac{\Delta T_1 - \Delta T_2}{In (\dfrac{\Delta T_1}{\Delta T_2} )}[/tex]

Also;

[tex]\Delta T_1 = T_{h_{in}}- T_{c_{out}} \\ \\ \Delta T_1 = 300 -290 \\ \\ \Delta T_1 = 10 \ K[/tex]

[tex]\Delta T_2 = T_{h_{in}}- T_{c_{out}} \\ \\ \Delta T_2 = 292 -290 \\ \\ \Delta T_2 = 2\ K[/tex]

[tex]LMTD = \dfrac{10 -2}{In (\dfrac{10}{2} )}[/tex]

[tex]LMTD = \dfrac{8}{In (5)}[/tex]

LMTD = 4.97

Thus, the required heat exchanger area A is calculated by using the formula:

[tex]Q_H = UA (LMTD)[/tex]

where;

U = overall heat coefficient given as 1200 W/m².K

[tex]66.667 \times 10^6 = 1200 \times A \times 4.97 \\ \\ A= \dfrac{66.667 \times 10^6}{1200 \times 4.97} \\ \\ \mathbf{A = 11178.236 \ m^2}[/tex]

The mass flow rate:

[tex]Q_{H} = mC_p(T_{in} -T_{out} ) \\ \\ 66.667 \times 10^6= m \times 4.18 (300 -292) \\ \\ m = \dfrac{ 66.667 \times 10^6}{4.18 \times 8} \\ \\ \mathbf{m = 1993630.383 \ kg/s}[/tex]

Answer:

h = 105.98 m

Explanation:

We will use the third equation of motion here:

[tex]2gh= v_f^2-v_i^2[/tex]

where,

g = acceleration due to gravity = 9.81 m/s²

h = height = ?

vf = final speed = (102 mi/h)(1 h/3600 s)(1609.34 m/1 mi) = 45.6 m/s

vi = initial speed = 0 m/s

Therefore,

[tex]2(9.81\ m/s^2)h = (45.6\ m/s)^2-(0\ m/s)^2\\\\h = \frac{ (45.6\ m/s)^2}{2(9.81\ m/s^2)}[/tex]

h = 105.98 m

Answer:

The cycle that moves carbon from one part of the Earth to another is called the carbon cycle.

Explanation:

     The carbon cycle describes the process in which carbon atoms continually travel from the atmosphere to the Earth and then back into the atmosphere. Since our planet and its atmosphere form a closed environment, the amount of carbon in this system does not change. Where the carbon is located — in the atmosphere or on Earth — is constantly in flux.

     On Earth, most carbon is stored in rocks and sediments, while the rest is located in the ocean, atmosphere, and in living organisms. These are the reservoirs, or sinks, through which carbon cycles. Carbon is released back into the atmosphere when organisms die, volcanoes erupt, fires blaze, fossil fuels are burned, and through a variety of other mechanisms. In the case of the ocean, carbon is continually exchanged between the ocean’s surface waters and the atmosphere, or is stored for long periods of time in the ocean depths.

     Humans play a major role in the carbon cycle through activities such as the burning of fossil fuels or land development. As a result, the amount of carbon dioxide in the atmosphere is rapidly rising; it is already considerably greater than at any time in the last 800,000 years.

Answer:

b

Explanation:

Answer:

The answer is E., or "Plate Boundaries".

The word best describes the definition of the location of volcanoes is "plate boundaries". Therefore, option (E) is correct.

The lithosphere is broken into tectonic plates that undergo some large motions and the boundary regions between plates are called plate boundaries. Based on their motions there are three kinds of plate boundaries: divergent, convergent, and transform.

Divergent boundaries are moving away from one another and separate, they form a rift. As the gap widens, the underlying layer may be soft for molten lava underneath to push upward and resulting in the formation of volcanic islands.

Convergent boundaries move towards one another and collide, subduction usually takes place. The denser plate goes underneath the less dense one and the plate boundaries also experience buckling.

Transform boundaries slide alongside one another and are exposed to huge amounts of stress and strain and are momentarily held in place. The two plates succeed in moving with respect to one another and cause earthquakes.

Learn more about plate boundaries, here:

https://brainly.com/question/18256552

#SPJ5

Solution :

Mass is varied keeping frequency constant.

Wavelength, λ  [tex]$=\frac{2l}{n}$[/tex]

where length of spring = l

           number of segments = n

Velocity, v = λ x f

                 = [tex]$\sqrt{\frac{T}{\mu}}$[/tex]

[tex]$\mu $[/tex] =  mass density, T = tension in string

[tex]$T=\frac{4 \mu l^2f^2}{n^2}$[/tex]

[tex]$T=mg = \frac{4 \mu l^2f^2}{n^2}$[/tex]  , n = 2

[tex]$T = (m-2.2)g = \frac{4 \mu l^2f^2}{n^2}, n = 5$[/tex]

[tex]$\Rightarrow \frac{m}{m-2.2}=\frac{25}{4}$[/tex]

[tex]$\Rightarrow m = 2.619\ kg$[/tex]

Therefore, μ = 0.002785 kg/ m

Frequency is varied keeping T constant

[tex]$T=\frac{4 \mu l^2f^2}{n^2}, f=60 , \ \ n = 2$[/tex]

[tex]$T=\frac{4 \mu l^2f^2}{n^2}, f=? , \ \ n = 7$[/tex]

[tex]$\Rightarrow \frac{60^2}{4}=\frac{f^2}{49}$[/tex]

f = 210 Hz

Answer:

(a) a = 2.44 m/s²

(b) s = 63.24 m

Explanation:

(a)

We will use the second equation of motion here:

[tex]s = v_it+\frac{1}{2}at^2[/tex]

where,

s = distance covered = 47 m

vi = initial speed = 0 m/s

t = time taken = 6.2 s

a = acceleration = ?

Therefore,

[tex]47\ m = (0\ m/s)(6.2\ s)+\frac{1}{2}a(6.2\ s)^2\\\\a = \frac{2(47\ m)}{(6.2\ s)^2}[/tex]

a = 2.44 m/s²

(b)

Now, we will again use the second equation of motion for the complete length of the inclined plane:

[tex]s = v_it+\frac{1}{2}at^2[/tex]

where,

s = distance covered = ?

vi = initial speed = 0 m/s

t = time taken = 7.2 s

a = acceleration = 2.44 m/s²

Therefore,

[tex]s = (0\ m/s)(6.2\ s)+\frac{1}{2}(2.44\ m/s^2)(7.2\ s)^2\\\\[/tex]

s = 63.24 m

Answer: 4.94cm³

Explanation:

Data;

ρ = 1.59g/cm³

mass = 7.85g

volume = ?

density = mass / volume

ρ = m / v

v = m / ρ

v = 7.85 / 1.59

v = 4.94cm³

Explanation:

if the current is 1A

V=iR

V= 1 × 8

V = 8volts