Answer:
sure if its easy im jp ill help u
Explanation:
Ok, assuming "mj" in the question is Megajoules MJ) you need a total amount of rotational kinetic energy in the fly wheel at the beginning of the trip that equals
(2.4e6 J/km)x(300 km)=7.2e8 J
The expression for rotational kinetic energy is
E = (1/2)Iω²
where I is the moment of inertia of the fly wheel and ω is the angular velocity.
So this comes down to finding the value of I that gives the required energy. We know the mass is 101kg. The formula for a solid cylinder's moment of inertia is
I = (1/2)mR²
We want (1/2)Iω² = 7.2e8 J and we know ω is limited to 470 revs/sec. However, ω must be in radians per second so multiply it by 2π to get
ω = 2953.1 rad/s
Now let's use this to solve the energy equation, E = (1/2)Iω², for I:
I = 2(7.2e8 J)/(2953.1 rad/s)² = 165.12 kg·m²
Now find the radius R,
165.12 kg·m² = (1/2)(101)R²,
√(2·165/101) = 1.807m
R = 1.807m
The answer is: the building codes, which are a set of rules that regulate the conditions that a building must meet. Those requirements are very important to guarantee safety of both the people who are building it and the people who are going to work or live inside of the building in the future
Answer:
The answer is B
Explanation:
The absorption happens when photons from light hit atoms and molecules, and they vibrate because of that specific interaction. Then the heat ejects from the object in the format of thermal energy.
Our sun is a medium mass star, so it wouldn't be too different from the sun's life cycle. It is born, lives for about 10 billion years and then dies. ... As a medium mass star nears the end of its life, it runs out of hydrogen which it has been fusing onto helium in its core for its whole life.
