A dish is given to you, which contains a blackish-yellow powder. When you move a magnet over it, you are amazed to see black par
ticles, (which you find out are iron) fly upwards and get stuck to the magnet, and all that's left in the dish is a yellow powder, which you discover to be sulfur. Was your original powder an element, compound or mixture?
In the case of the blackish-yellow powder, the black color is due to the presence of a iron and yellow color is due to sulfur. As the iron has retained its original properties it has got attached to the magnet. Thus the blackish-yellow powder is considered a mixture.
The function of the current with respect to time is the derivative of the charge function with respect to time t. We can apply chain rule to differentiate it:
