Physics is known as the fundamentals of science, as all the branches of science, whether it is biology, chemistry, ecology, botany, environmental science, geology, geography, and more all follow the laws of physics, such as laws of thermodynamics, etc. Chemistry is existent because of physics due to the Conservation of mass. Once you get to a much deeper level of science, you will notice that all the fields of science start to blend together and all add up to one huge painting!
That's not true people that have a broken leg use crutches and the constant lifting of their own body weight will help them gain muscle
Answer:
1. In a coal-fired power plant, chemical energy is first converted to thermal energy. TRUE.
The chemical energy in the coal is converted to thermal energy when the coal is burnt to produce steam.
2. In a coal-fired power plant, approximately 2/5 of original energy in the coal is lost to heat. FALSE.
Approximately 3/5 of the original energy is lost not 2/5 so this statement is false.
3. The molecules in cold air move faster than in hot air. FALSE.
Molecules with more heat move faster than molecules with less. Molecules in cold air therefore, will move slower than molecules in hot air.
Answer:
v = 10 [m/s].
Explanation:
The largest mass is that of 4 [kg], in this way the momentum can be calculated by means of the product of the mass by velocity.

where:
P = momentum [kg*m/s]
m = mass = 4 [kg]
v = velocity = 5 [m/s]
Now the momentum:
![P=4*5\\P=20[kg*m/s]](https://tex.z-dn.net/?f=P%3D4%2A5%5C%5CP%3D20%5Bkg%2Am%2Fs%5D)
This same momentum is equal for the other mass, in this way we can find the velocity.
![P=m*v\\20=2*v\\v=10[m/s]](https://tex.z-dn.net/?f=P%3Dm%2Av%5C%5C20%3D2%2Av%5C%5Cv%3D10%5Bm%2Fs%5D)