Potential Difference and power Flashcards
How is a bulb powered?
electrons deliver energy from the battery to the bulb
each electron moves around the cricuit and takes a fixed amount of energy from the battery as it passes through
electron are resupplied with energy as they re-enter the battery via the positive terminal
What is potential difference?
the work done per unit of charge is the pd or voltage across a component
What is the equation for work done?
work done = volts x charge
How does a heater work?
work done on the device is transferred as thermal energy
this happens because the charge carriers repeatedly collde with atoms in the device and transfer energy to them
atoms vibrate more and the resistor becomes hotter
How does a electric motor work?
electrons need to be forced through the wires of the spinning motor coil against the opposing force on the electrons due to the motors magnetic field
What is the equation for power?
P=IV
