# Electricity- 2 objects of different power on same battery.

by hasankamal007
Tags: battery, electricity, objects, power
 HW Helper P: 3,443 Electricity- 2 objects of different power on same battery. mfb is right. Maybe it needs a bit more explanation? Voltage is energy per charge (since we are ignoring the effect of magnetic fields). And we can also say that current $I$ is the charge going through per second. So current times voltage is the energy lost per second (i.e. the power). This gives us: $P=VI$ We also know for ohmic resistors that $V=IR$ And rearranging these two equations gives: $$P= \frac{V^2}{R}$$ So the power used is inversely proportional to the resistance (since voltage is the same in both cases). To put all this into an intuitive explanation: A greater current means more power because more charge carriers are moving through the potential difference. And to get a greater current, we can use a resistor with less resistance.