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
OLga [1]
3 years ago
11

A power station burns 75 kilograms of coal per second. Each kg of coal contains 27 million joules of energy.

Physics
1 answer:
Kaylis [27]3 years ago
3 0

Answer:

Explanation:

a )

one kg of coal gives energy of 27 x 10⁶ J

75 kg of coal gives energy of 27 x 10⁶ x 75 J

So rate which energy is coming out of coal per second

= 27 x 10⁶ x 75 J

= 2025 x 10⁶ J /s

2025 million watts .

b ) energy output = 800 million watts

efficiency = (800 / 2025) x 100

= 39.5 % .

You might be interested in
How is the pressure of a gas related to its concentration of particles?A) Pressure will expand a gas, enlarging its volume and r
Lesechka [4]

Answer:

C) Pressure will compress a gas, reducing its volume and giving it a greater density and concentration of particles.

Explanation:

At constant temperature, pressure and volume are inversely related.

P V = constant

\Rightarrow P \propto \frac{1}{V}

As the pressure increases, the gas compresses, the particles come closer reducing the volume of gas.

As we know, with decrease in volume, density increases.

Density = \frac{Mass}{Volume}

Density \propto \frac{1}{Volume}

Thus, the pressure of a gas is directly related to concentration of particles. Increase in pressure causes increase in concentration of the particles.

8 0
3 years ago
What happens when energy is added to a liquid without changing its phase
djverab [1.8K]

the mole of the substance will boiling or freezing point ,

all of it melt or boiled,but the temperature won't change

water boil at 212°F (100°C)

energy remove and it will be ice

if energy is added to the matter

hope you understand!!!!!!!!!!!

5 0
3 years ago
Electromagnetic waves are not mechanical waves, which means they can<br> travel in a:
svet-max [94.6K]
<h3>Answer:</h3>

Vacuum

<h3>Explanation:</h3>

Concept being tested: Waves and types of waves

To answer the question we need to define both electromagnetic waves and mechanical waves.

  • Waves can be classified as either electromagnetic waves and mechanical waves based on whether they require a material medium for transmission or not.
  • Electromagnetic waves do not require a material medium for transmission and can travel through a vacuum.
  • Mechanical waves, on the other hand, are waves that require a material medium for transmission.

What are examples of electromagnetic waves and mechanical waves?

  • Examples of electromagnetic waves include gamma rays, radio waves, visible light, etc.
  • Examples of mechanical waves include sound waves and water waves.

Therefore, the answer to our question is;

  • Electromagnetic waves are not mechanical waves, which means they can travel in a vacuum.
4 0
4 years ago
How does speed effect momentum?
drek231 [11]
Momentum = mass * speed
Speed is proportional to momentum; i.e. having twice the speed would result in double the momentum, a lower speed = smaller momentum, etc
7 0
3 years ago
Small, solid pieces of material that come from rocks or living things are called ____
Over [174]
It will be sediment, that's the only thing can be in a rock and it's a living thing. Sediment is part of a rock so that's your answer this is a 7th grade question not that hard I'm in the 5th grade no officence but enjoy your answer
6 0
4 years ago
Other questions:
  • Describe the proton gradient generated by the electron transport chain
    15·1 answer
  • An astronaut in an orbiting spacecraft attaches a mass m to a string and whirls it around in uniform circular motion. The radius
    13·1 answer
  • A pulley system has an efficiency of 74.2%. If you perform 200 J of work, how
    5·1 answer
  • The peak intensity of radiation from a star named sigma is 2 x 10^6 mmkay. What is the average surface temperature of Sigma roun
    7·2 answers
  • A student drove to the university from her home and noted that the odometer reading of her car increased by 12.0 km. The trip to
    13·1 answer
  • Lucy took 3 hours to cover 2/3 of a journey. She covered the
    5·1 answer
  • An electric furnace is to melt 40 kg of aluminium/hour. The initial temperature of aluminium is 32°C. Given that aluminium has s
    12·1 answer
  • Which of the following is a variable property for a gas? Select all that apply.
    15·1 answer
  • HELPPP!!!!
    6·1 answer
  • According to our theory of solar system formation, why do we find some exceptions to the general rules and patterns of the plane
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!