<span>Answer:
F(x) = ax^2 - bx
or
F(x) = ax² - bx
F(x) = 30x² - 6x
â«F(x)dx = â«(30x² - 6x)dx
as this is evaluated from zero to x
W = 10x³ - 3x² <===ANS
W = 10(0.42³) - 3(0.42²) - [10(0³) - 3(0²)]
W = 0.212 J <===ANS
W = 10(0.72³) - 3(0.72²) - [10(0.42³) - 3(0.42²)]
W = 1.966 J <===ANS</span>
<span>Charging by friction occurs, Electrons are transferred when one object rubs against another.
Another example of this would be socks on carpet.
Hope this helps!</span>
<span>Your flexibility decreases. But if you exercise or stretch a few times a week you can slow down the process </span>
In the circuit outside of the battery the electrons have to expend all of their energy on the internal resistance of the battery which causes heating