Ask question

Ask question

All categories

3 years ago

7

A wind turbine takes in energy from wind with the goal of converting it into electrical energy. Much of the wind energy is also

converted into the kinetic energy of the spinning turbine and heat lost to the air around it. An illustration of a windmill with a wide arrow away from it labeled kinetic energy of wind 3000 J and it separates into 3 different arrows, one labeled electric energy 750 J, the second labeled heat 750 J and the third which is the widest labeled kinetic energy of turbine blank J. If the goal of the turbine is to put out electric energy, what is the efficiency of the turbine? 25% 50% 75% 100%.

1 answer:

kondor19780726 [428]3 years ago

5 0

The efficiency of the turbine is 50%.

The given parameters:

<em>Kinetic energy of the wind, E = 3000 J</em>
<em>Output electrical energy, E(out) = 750 J</em>
<em>Energy lost to heat, E(lost) = 750 J</em>
<em>Kinetic energy of the turbine, E(in) = ?</em>

The kinetic energy of the turbine which is the input energy is calculated as follows;

E(in) = 3000 - (750 + 750)

E(in) = 1500 J

The efficiency of the turbine is calculated as follows;

$E_f_f = \frac{E_{(out)}}{E_{(in)}} \times 100\%\\\\E_f_f = \frac{750}{1500} \times 100\%\\\\E_f_f = 50 \%$

Thus, the efficiency of the turbine is 50%.

Learn more about efficiency of turbine here: brainly.com/question/2009210

You might be interested in

A block of unknown mass is attached to a spring with a spring constant of 7.00 N/m 2 and undergoes simple harmonic motion with a

KatRina [158]

Answers:

a) $0.80 kg$

b) $2.12 s$

c) $1.093 m/s^{2}$

Explanation:

We have the following data:

$k=7 N/m$ is the spring constant

$A=12.5 cm \frac{1 m}{100 cm}=0.125 m$ is the amplitude of oscillation

$V=32 cm/s=0.32 m/s$ is the velocity of the block when $x=\frac{A}{2}=0.0625 m$

Now let's begin with the answers:

<h3>a) Mass of the block</h3>

We can solve this by the conservation of energy principle:

$U_{o}+K_{o}=U_{f}+K_{f}$ (1)

Where:

$U_{o}=k\frac{A^{2}}{2}$ is the initial potential energy

$K_{o}=0$ is the initial kinetic energy

$U_{f}=k\frac{x^{2}}{2}$ is the final potential energy

$K_{f}=\frac{1}{2} m V^{2}$ is the final kinetic energy

Then:

$k\frac{A^{2}}{2}=k\frac{x^{2}}{2}+\frac{1}{2} m V^{2}$ (2)

Isolating $m$ :

$m=\frac{k(A^{2}-x^{2})}{V^{2}}$ (3)

$m=\frac{7 N/m((0.125 m)^{2}-(0.0625 m)^{2})}{(0.32 m/s)^{2}}$ (4)

$m=0.80 kg$ (5)

<h3>b) Period</h3>

The period $T$ is given by:

$T=2 \pi \sqrt{\frac{m}{k}}$ (6)

Substituting (5) in (6):

$T=2 \pi \sqrt{\frac{0.80 kg}{7 N/m}}$ (7)

$T=2.12 s$ (8)

<h3>c) Maximum acceleration</h3>

The maximum acceleration $a_{max}$ is when the force is maximum $F_{max}$ , as well :

$F_{max}=m.a_{max}=k.x_{max}$ (9)

Being $x_{max}=A$

Hence:

$m.a_{max}=kA$ (10)

Finding $a_{max}$ :

$a_{max}=\frac{kA}{m}$ (11)

$a_{max}=\frac{(7 N/m)(0.125 m)}{0.80 kg}$ (12)

Finally:

$a_{max}=1.093 m/s^{2}$

5 0

3 years ago

Which of the following would be the least reliable source of information?

Ksenya-84 [330]

I'd say a weekly news magazine.

7 0

3 years ago

¿ qué es un motor de explosión?

ArbitrLikvidat [17]

Answer:

es un motor de combustión interna con encendido por chispa.

5 0

3 years ago

You throw a basketball and a tennis ball across the classroom so that each ball has the exact same momentum. Explain how this is

Helga [31]

Answer:

It is possible by increasing the speed of the tennis ball by a factor of (Mass of the tennis ball)/(Mass of the basketball)

Explanation:

The momentum of a body = The bod's mass × The body's velocity

Therefore, the momentum of a given mass of an object, such as a tennis ball can be increased by increasing the velocity or speed of the object. Whereby the speed of the ball, v₁, is increased such that the momentum of the basketball and the tennis ball will be the same, is given by the following equation

Mass of the basketball × v₂ = Mass of the tennis ball × v₁

Therefore, v₁/v₂ = (Mass of the tennis ball)/(Mass of the basketball)

7 0

3 years ago

A rocket's mass decreases as it burns fuel. the equation of motion for a rocket in vertical flight can be obtained from newton's

Talja [164]

<span>The equation of motion for a rocket in vertical flight can be obtained from newton’s second law of motion and is constant-mass system. The equation of motion for a body mass varies with time and mass. When force acts on rocket, the rocket will accelerate in the direction of force. Therefore, force is equal to the change in momentum per change in time. For constant mass, force equals mass times acceleration.</span>

4 0

4 years ago