The 4 m board's center of mass is 2 m so the pivot point is somewhere between Tasha and 2 m (if you draw a picture it's going to make this clearer)
The mass of Tasha * her distance from the pivot point = the board's mass * distance from the pivot point. <span> Let d1 be the distance Tasha is from the pivot point. The board's center of mass from the pivot point is 2 m - d1 </span><span> 20 kg * d1 = 10 kg * (2m - d1) </span><span> Solve for d1, you should get 2/3 of a m for the distance Tasha is from the pivot or support point. The center of mass for the board is 1 1/3 m from the support point. </span>
Heat flows from hot to cold to lower the temperature of hot areas and increase temperature of cold areas. The end result is that the 2 areas have the same temperature, thus increasing entropy.
Since both heat and work can be measured and quantified, this is the same as saying that any change in the energy of a system must result in a corresponding change in the energy of the surroundings outside the system. In other words, energy cannot be created or destroyed.
