For Girls it's called estrogen
For boys it's testosterone
They each do different things to the sex and they each come at different time periods of their lives.
<span>The earth does no work on her if she's falling in the direction of frictional force. But suppose it does work on the woman i.e in the opposite direction, N. Then we have F = mg where g is acceleration due to grav. So F = 68 * 9.8 = 666.4 Newton. Then work done = force * distance = 666.4 * 100 = 666400</span>
Thermal-energy flow between objects is conserved and always flows from the warmer object to the cooler object.
Here 'conserved' means that the amount of thermal energy lost of by one body is exactly equal to the amount of thermal energy gained by another body, which is the statement of the first law.
According to second law, we do not see objects warming up on their own. For example, if we have a cup of coffee left to itself, we would always see that it cools down. Here, thermal energy is being transferred from warmer object (coffee) to cooler objects (the air in the room).
