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
8090 [49]
3 years ago
10

Given that coal used by electric power plants has a heating value of 27.5 million btus metric ton (25 million btus per ton), det

ermine the number of kilograms (and pounds) of coal needed to produce 1 million btus of heat.
Physics
1 answer:
fredd [130]3 years ago
3 0

Answer:

• 36.4 kg of coal.

• 80 pounds of coal.

Explanation:

Using proportionality constant,

Mass of coal = 1,000,000/27,500,000 btus/metric ton

= 0.0364 metric tons of coal

Mass of coal = 1,000,000/25,000,000 btus/ton

= 0.04 tons of coal.

Converting metric tons to kilogram,

1 metric ton = 1000kg,

0.0364 metric ton;

= 36.4 kg of coal.

Converting tons to pounds,

1 ton = 2000 pounds,

0.04 metric ton;

= 80 pounds of coal.

You might be interested in
I need to choose a theme for my physics assignment My experiment is finding g
Kobotan [32]
<h3>Question:</h3>

How to find g (acceleration due to gravity)

<h3>Solution:</h3>

We know,

Acceleration due to gravity (g)

=  \frac{GM}{ {R}^{2} }

where, G = Gravitational constant

= 6.67 \times  {10}^{11} N {m}^{2}/k {g}^{2}  \\

M = Mass of the earth

= 6 \times  {10}^{24} \:  kg

R = Radius of the earth

= 6.4 \times  {10}^{6} m

Putting these values of G, M and R in the above formula, we get

g \:  =  \:  \frac{6.67 \times  {10}^{11} N {m}^{2}/k {g}^{2}   \times \: 6 \times  {10}^{24} \:  kg }{(6.4 \times  {10}^{6}m {)}^{2}  }  \\  = 9.8m/ {s}^{2}

So, the value of acceleration due to gravity is

9.8m/s ^{2}

Hope it helps.

Do comment if you have any query.

5 0
2 years ago
according to newton's first law of motion what is the reason for a ball throwing up in the airfall back to earth
skelet666 [1.2K]
The force of earth's gravitational field is always directed downwards (towards the center of the earth. When the ball is thrown up, it is going against the earth's gravitational field and so, the earth's gravitational force pulls it back down, accelerating it downwards.
5 0
3 years ago
A rocket moves upward from rest with an acceleration of 40 m/s2 for 5 seconds. It then runs out of fuel and continues to move up
Snezhnost [94]

Answer:

Maximum height of rocket  = 2538.74 m

Explanation:

We have equation of motion s = ut + 0.5 at²

For first 5 seconds

          s = 0 x 5 + 0.5 x 40 x 5² = 500 m

Now let us find out time after 5 seconds rocket move upward.

We have the equation of motion v = u + at

After 5 seconds velocity of rocket

         v = 0 + 40 x 5 = 200 m/s

After 5 seconds the velocity reduces 9.8m/s per second due to gravity.

Time of flying after 5 seconds

          t=\frac{200}{9.81}=20.38s

Distance traveled in this 20.38 s

          s = 200 x 20.38 - 0.5 x 9.81 x 20.38² = 2038.74 m

Maximum height of rocket = 500 +2038.74 = 2538.74 m

6 0
3 years ago
IN WHAT CONDITION DO SOUND ECHO
DerKrebs [107]

Answer:

The conditions necessary for hearing the echo. The distance between the sound source and the reflecting surface must not be less than 17 metres where the time period between hearing the original sound and its echo should not be less than 0.1 of a second.

6 0
2 years ago
Which property of light remains unchanged when it enters a different medium?
Amiraneli [1.4K]
The FREQUENCY of light remains unchanged once it leaves the source.
3 0
3 years ago
Read 2 more answers
Other questions:
  • What are the Rules of magnetism
    12·1 answer
  • Your car burns gasoline as you drive up a mountain road. What energy transformation is taking place?
    10·2 answers
  • Find the smallest positive phase of the mass on a spring that undergoes simple harmonic motion if at time t = 0.1 s the position
    12·1 answer
  • HELP PLEASE! THANKS!!
    11·2 answers
  • What is the name of the special science tool he can use to predict genetic outcome?
    9·1 answer
  • . The inner and outer surfaces of a 4-m × 7-m brick wall of thickness 30 cm and thermal conductivity 0.69 W/m-K are maintained a
    5·1 answer
  • how can the thumb and fingers of your right hand be used to identify the direction of a magnetic field?
    11·1 answer
  • Which of the following will cause an increase in the mass of an object? (1 point)
    13·1 answer
  • _________ is a change in the position of a body with respect to time relative to a reference point.
    8·2 answers
  • PLEASE SOMEONE HELP ME PLEASE
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!