Popping a cocktail of supplements every day might be doing you more harm than good

Today on the BBC: Popping a cocktail of supplements every day might be doing you more harm than good. They say “those which are particularly toxic to the liver when taken in high doses include vitamin A, glutamine, ashwagandha and green tea extract.”

Passive sign convention

Today I learned about the passive sign convention in electric circuits. It is also known as “associated references”. When current is flowing into the positive terminal of a circuit element then the element is absorbing power. When current is flowing into the negative terminal of a circuit element then the element is providing power. P = VI and when P is positive the element is receiving power and when P is negative the element is providing power. In a complete circuit the sum of power is zero, the sources and loads are evenly balanced.