1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Korolek [52]
3 years ago
5

What does it mean that a form of energy might take more energy to harness than it provides? Are renewable resources always renew

able, or can they become non-renewable? Why aren't renewable resources used for everything that we use energy for? Explain.
Physics
1 answer:
frez [133]3 years ago
6 0
A form of energy might take more energy to harness than it provides because of dissipated energy. During the transformation process, not all of the energy will be converted to useful energy. Some of the energy are dissipated in the form of heat. Renewable resources are resources that are replenished at a faster rate than they are used. They become non-renewable when these resources are used up at a faster rate than they are replenished. We don't use renewable resources for everything that we use energy for because the energy transformation might be inefficient or requires a lot of capital and maintenance.
You might be interested in
g The electric power needs of a community are to be met by windmills with 40-m-diameter rotors. The windmills are to be located
Ksenya-84 [330]

Answer:

Explanation:

Given Data

The diameter of the wind mills is d = 40m

Velocity of the air is V = 6 m / s

Required power output is:  P ₀ = 2100 k W

Expression to calculate the exergy of the air is

E = V ² / 2

Substitute the value in above expression

E = ( 6 m / s ) ² / 2

E = 18 m ² / s ² x (1kJ/kg / 1000m²/s²)

E = 0.018 k J / k g

Expression to calculate the density of the air is

P v =m R T

m /v = P  /RT ⋯ ⋯( I )

Here  

m  is the mass of the air,  

v  is the volume of the air,  

P  is the atmospheric pressure,  

T  is the standard temperature at the atmospheric pressure and  

R  is the gas constant

As the density is

ρ = m /V

Substitute the value in expression (I)

ρ = 101  kP a /( 0.287 k J / k g ⋅ K ) ( 298 K )

ρ = 1.180 k g / m ²

Expression to calculate the mass flow rate is

m = ρ A V ⋯ ⋯ ( I I )

Here  A  is the area of the windmill

Expression to calculate the  A  is

A = π /4  d ²

Substitute the value in above expression

A = π /4 ( 40 m ²)

A = 1256.63 m ²

Substitute the value in expression (II)

m = ( 1.180 k g / m ³) ( 1256.63 m ²) ( 6 m / s )

m = 8896.94  k g / s

Expression to calculate the maximum power available to the windmill is

P w = m ( V ² /2 )

Substitute the value in above expression

P w = 8896.94  k g / s ( (6m/s)²/2 )

P w = 160144.92 W  × ( 1 W /1000 k W )

P w = 160.144 k W

Expression to calculate the number of windmills required is

n = P o /P w

Substitute the value in above expression

n=2100kw/160.144kw

n=13.11

8 0
3 years ago
A piece of wood on top of an ocean wave stays in the same location, only moving up and down as the wave passes. It is energy tha
Ierofanga [76]

Answer:

Hey

Yes, this is true.

As some people have it wrong, waves in the water (ocean) are not waves of moving water, rather the wave is moving through the water. A wave is a disturbance of a medium not the meduim moving.

8 0
3 years ago
What must be the acceleration of a train in order for it to stop 12 m/s in a distance if 541 m
earnstyle [38]

Answer:

The acceleration of the train must be - 0.133 m/s²

Explanation:

Lets explain how to solve the problem

A train in order for it to stop 12 m/s in a distance if 541 m

That means the initial velocity of the train is 12 m/s

Its final velocity is zero (stop)

The distance it covers is 541 m

We want to find its acceleration

The acceleration will be negative quantity because the train reduced its

velocity from 12 m/s to zero

We need rule contains velocity, acceleration and distance

So we will use ⇒<em> v² = u² + 2as</em>, where v is the final velocity, u is the

initial velocity, a is the acceleration and s is the distance

v = 0, u = 12 m/s, s = 541 m

Substitute these values in the rule

(0)² = (12)² + 2(a)(541)

0 = 144 + 1082 a

Subtract 144 from both sides

-144 = 1082 a

Divide both sides by 1082

- 0.133 = a

<em>The acceleration of the train must be - 0.133 m/s²</em>

3 0
3 years ago
The escape velocity is defined to be the minimum speed with which an object of mass m must move to escape from the gravitational
s344n2d4d5 [400]

Answer:

v = √2G M_{earth} / R

Explanation:

For this problem we use energy conservation, the energy initiated is potential and kinetic and the final energy is only potential (infinite r)

        Eo = K + U = ½ m1 v² - G m1 m2 / r1

        Ef = - G m1 m2 / r2

When the body is at a distance R> Re, for the furthest point (r2) let's call it Rinf

       Eo = Ef

       ½ m1v² - G m1 M_{earth} / R = - G m1 M_{earth} / R

      v² = 2G M_{earth} (1 / R - 1 / Rinf)

If we do Rinf = infinity     1 / Rinf = 0

       v = √2G M_{earth} / R

      Ef = = - G m1 m2 / R

The mechanical energy is conserved  

 

      Em = -G m1  M_{earth} / R

      Em = - G m1  M_{earth} / R

     R = int        ⇒  Em = 0

6 0
2 years ago
A student lifts 100 N of books 1 m to his shoulder. He walks forward
Delvig [45]

<em>Hope</em><em> </em><em>this</em><em> </em><em>will</em><em> </em><em>help</em><em> </em><em>u</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>:</em><em>)</em>

<em>✌</em><em>✌</em><em>✌</em><em>✌</em><em>✌</em><em>✌</em>

7 0
3 years ago
Other questions:
  • A body 'A' of mass 1.5kg travelling along the positive X-axis with speed of 4.5m/s collides with another body 'B' of mass 3.2kg,
    14·1 answer
  • One degree kelvin equals one degree Fahrenheit ? True or false
    10·1 answer
  • Suppose you observe that at night, the air just above the ground feels cooler than the air above it. then in the middle of a sun
    15·1 answer
  • a motorcycle starting from rest has an acceleration of 2.6m/s how long does it take the motorcycle to travel a distance of 120
    6·1 answer
  • How many lymphatic organs are located in the abdominal cavity
    11·1 answer
  • A series circuit is composed of two resistors:
    14·1 answer
  • An object has rotational inertia I. The object, initially at rest, begins to rotate with a constant angular acceleration of magn
    8·1 answer
  • A force that opposes motion in moving parts is friction. <br><br> A. true<br> b false
    6·2 answers
  • a moving truck takes a much longer time to stop than that taken by a car when brakes are pressed at the same time​
    14·1 answer
  • Which would most likely form a homogenous mixture?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!