Well if you go to Quiz-let it gives the answer the mass of a mole of compound is determined by adding the atomic masses of the atoms making up the molecules
That's the answer on that picture
To calculate for the final temperature, we need to remember that the heat rejected should be equal to the absorbed by the other system. We calculate as follows:
Q1 = Q2
(mCΔT)1 = (mCΔT)2
We can cancel m assuming the two systems are equal in mass. Also, we cancel C since they are the same system. This leaves us,
(ΔT)1 = (ΔT)2
(T - 80) = (0 - T)
T = 40°C
Answer:
Option (3)
Explanation:
Wind energy is directly derived from the wind. In the places where wind blowing is quite frequent, there wind mills are being set up, and the turbines in it rotates due to the prevailing wind. Due to this continuous motion of turbines, it collects the wind energy and it is being transferred into electrical energy.
It is cost-effective and does not produce any kind of pollution and is completely a renewable energy, that it can generated again and again.
It does have certain drawbacks also, because <u>the area may sometime do not experience constant wind, due to which it cannot store energy. So frequent wind blowing areas are the best place to set up windmills</u>.
Thus, the correct answer is option (3)
