What was the important new result shown by joules experiment involving paddles stirring known quantities of water?

An atom that has gained or lost electrons is called an _

You have a resistor and a capacitor of unknown values. first, you charge the capacitor and discharge it through the resistor. by monitoring the capacitor voltage on an oscilloscope, you see that the voltage decays to half its initial value in 3.00 ms . you then use the resistor and capacitor to make a low-pass filter. what is the crossover frequency fc?

What happens to light when it strikes the inside surface of a smooth, curved mirror?