What two forces could slow down your marble

Air enters a turbine operating at steady state at 8 bar, 1400 K and expands to 0.8 bar. The turbine is well insulated, and kinet

vladimir2022 [97]

To solve this problem it is necessary to apply the concepts related to the adiabatic process that relate the temperature and pressure variables

Mathematically this can be determined as

$\frac{T_2}{T_1} = (\frac{P_2}{P_1})^{(\frac{\gamma-1}{\gamma})}$

Where

$T_1 =$ Temperature at inlet of turbine

$T_2 =$ Temperature at exit of turbine

$P_1 =$ Pressure at exit of turbine

$P_2 =$ Pressure at exit of turbine

The steady flow Energy equation for an open system is given as follows:

$m_i = m_0 = m$

$m(h_i+\frac{V_i^2}{2}+gZ_i)+Q = m(h_0+\frac{V_0^2}{2}+gZ_0)+W$

Where,

m = mass

$m_i$ = mass at inlet

$m_0$ = Mass at outlet

$h_i$ = Enthalpy at inlet

$h_0$ = Enthalpy at outlet

W = Work done

Q = Heat transferred

$V_i$ = Velocity at inlet

$V_0$ = Velocity at outlet

$Z_i$ = Height at inlet

$Z_0$ = Height at outlet

For the insulated system with neglecting kinetic and potential energy effects

$h_i = h_0 + W$

$W = h_i -h_0$

Using the relation T-P we can find the final temperature:

$\frac{T_2}{T_1} = (\frac{P_2}{P_1})^{(\frac{\gamma-1}{\gamma})}$

$\frac{T_2}{1400K} = (\frac{0.8bar}{8nar})^{(\frac{1.4-1}{1.4})}$

$T_2 = 725.126K$

From this point we can find the work done using the value of the specific heat of the air that is 1,005kJ / kgK

So:

$W = h_i -h_0$

$W = C_p (T_1-T_2)$

$W = 1.005(1400-725.126)$

$W = 678.248kJ/Kg$

Therefore the maximum theoretical work that could be developed by the turbine is 678.248kJ/kg

5 0

4 years ago

Suppose the electric company charges 10 fils per kW h. How much does it cost to use a 125 watt lamp 4 hours a day for 30 days? A

ivanzaharov [21]

Answer:

150 fils

Explanation:

Power = 125 Watt

Time 4 hours a day

Energy per day = Power x time per day = 125 x 4 = 500 watt hour

Energy for 30 days = 500 x 30 watt hour = 15000 watt hour = 15 KWH

Cost of 1 KWH = 10 fils

Cost of 15 KWH = 15 x 10 = 150 fils

5 0

4 years ago

True or False?<br><br> There are equal numbers of protons and electrons in neutral atoms.

Alecsey [184]

Answer: True
Hope this helped

8 0

3 years ago

Read 2 more answers

The path a projectile takes is known as the Question 1 options: vertical component trajectory horizontal component parabola Ques

Firdavs [7]

1. Trajectory

The path a projectile is called a trajectory in physics. It has a vertical component and even makes a parabola, but if we are talking about physics, it is trajectory.

2. A person sitting in a chair

Projectiles can be defined as an object that is in flight. So it has to be in the air. Since a person sitting in a chair is not in flight, then it is NOT a projectile. (Unless you throw the person in the air while he is in the chair)

3. 490 meters

We have the formula and our given:

d = 1/2gt²

Just plug in the values to get your answer:

d = 1/2(-9.8m/s²)(10s)²

d = (-4.9m/s²)(100s²)

d = -490m

So since height is a scalar value, just take out the negative sign.

4. 65 m/s

Again we have our formula and given:

$v=\dfrac{d}{t}$

So we just plug in our values:

$v=\dfrac{650m}{10s}$

$v=650m/s$

5. True

A projectile, if you will notice its trajectory moves both horizontally and vertically. The horizontal motion is what we call the x-component and the vertical is called the y-component. This is what gives it its' curved path.

6. False

An ellipse is an oval-shaped path. A projectile does not move in a circular/oval path. It travels a curved path. It can be parabolic. It is curved but it does not follow a circular path.

7. The vertical component always equals the horizontal component

This is false. Vertical component is different from the horizontal component. The horizontal component is not influenced by gravity only the vertical component. So in short, the horizontal component is the same throughout, but the vertical component changes over time.

8. Constant

Like mentioned above, the horizontal movement is constant or it does not change. This is because a projectile is defined also as an object that is influenced solely by gravity.

9. Vertical velocity decreases

This is because the movement is against the pull of gravity. It will continue to decrease until it will eventually come to a stop and start to descend. As it descends it increases.

10. Vertical velocity increases

I guess explained it above. As the object descends, the vertical movement increases. This is why you can actually die at certain heights. It increases as the time in flight increases. So the longer in flight, the faster it will get.

3 0

4 years ago

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Charges of 4.0 μC and −6.0 μC are placed at two corners of an equilateral triangle with sides of 0.10 m. What is the magnitude o

jek_recluse [69]

Answer:

4.763 × 10⁶ N/C

Explanation:

Let E₁ be the electric field due to the 4.0 μC charge and E₂ be the electric field due to the -6.0 μC charge. At the third corner, E₁ points in the negative x direction and E₂ acts at an angle of 60 to the negative x - direction.

Resolving E₂ into horizontal and vertical components, we have

E₂cos60 as horizontal component and E₂sin60 as vertical component. E₁ has only horizontal component.

Summing the horizontal components we have

E₃ = -E₁ + (-E₂cos60) = -kq₁/r²- kq₂cos60/r²

= -k/r²(q₁ + q₂cos60)

= -k/r²(4 μC + (-6.0 μC)(1/2))

= -k/r²(4 μC - 3.0 μC)

= -k/r²(1 μC)

= -9 × 10⁹ Nm²/C²(1.0 × 10⁻⁶)/(0.10 m)²

= -9 × 10⁵ N/C

Summing the vertical components, we have

E₄ = 0 + (-E₂sin60)

= -E₂sin60

= -kq₂sin60/r²

= -k(-6.0 μC)(0.8660)/(0.10 m)²

= -9 × 10⁹ Nm²/C²(-6.0 × 10⁻⁶)(0.8660)/(0.10 m)²

= 46.77 × 10⁵ N/C

The magnitude of the resultant electric field, E is thus

E = √(E₃² + E₄²) = √[(-9 × 10⁵ N/C)² + (46.77 10⁵ N/C)²) = (√226843.29) × 10⁴

= 476.28 × 10⁴ N/C

= 4.7628 × 10⁶ N/C

≅ 4.763 × 10⁶ N/C

8 0

3 years ago