Answer:
120,000J
Corrected question;
In one hour, coal supplies 500 000 J of energy. The wasted energy amounts to 380 000 J. How much useful energy is produced in one hour?
Explanation:
Given;
Total energy Et = 500,000 J
Wasted Energy Ew = 380,000J
The amount useful energy is the amount of energy that is available for supply.
This can be derived by subtracting the wasted energy from the total energy.
Useful energy = Total Energy - wasted energy
Eu = Et - Ew
Substituting the given values;
Eu = 500,000J - 380,000
Eu = 120,000 J
The amount of useful energy produced in one hour is 120,000 J
Answer:
The value is 
Explanation:
From the question we are told that
The mass of the bullet is 
The mass of the wood is 
The height attained by the combined mass is 
Generally according to the law of energy conservation
Here 
is the kinetic energy of the bullet before collision.
and 
is the potential energy of the combined mass of bullet and wood at the height h which is mathematically represented as
![PE_m = [m_b + m_w] * g * h](https://tex.z-dn.net/?f=PE_m%20%20%3D%20%20%5Bm_b%20%20%2B%20m_w%5D%20%2A%20%20g%20%2A%20%20h)
So
![KE_b =PE_c = [0.005 + 0.90] * 9.8 *0.08](https://tex.z-dn.net/?f=KE_b%20%3DPE_c%20%20%20%3D%20%5B0.005%20%20%2B%200.90%5D%20%2A%209.8%20%2A0.08)
=>
A) 0
because all of the forces cancel out, so it is not moving with balanced forces.
Answer:
A. nuclear fusion reactions
C. it's still hot from the big bang
Explanation:
The inside of the earth is hot due to some reasons. This heat provides the internal energy the drives processes within the earth interior. Here are some of the ways in which the heat has accumulated:
- Nuclear reactions within the earth interior by fusion and other radioactive processes releases a large amount of heat.
- Some heat accreted during the early formation of the earth and has not been lost till this day.
- Heating due to friction
These are some of the sources of the earth's internal heat.
