AMPS AND VOLTS ELECTRIC CURRENT Electrons flow through

AMPS AND VOLTS

ELECTRIC CURRENT Electrons flow through a conductor like water flows through a pipe. The electrons move in small groups along a conductor. These groups are referred to as Coulombs. 1 drop = millions of molecules 1 Coulomb = 6. 25 x 1018 electrons

Electric current is the measure of the rate at which electrons move past a given point in a circuit per second. CURRENT, CHARGE, and TIME can be related using the following formula: Current (A) = I=Q t Charge (C) Time (s) Units for Current are Amperes (A) = 1 C/s Using this formula, we can solve for all three variables: I=Q t t=Q I Q=Ixt

LET’S TRY SOME TOGETHER: CURRENT PROBLEMS Example One: What is the current moving through a wire (conductor) if 10 C of charge travels past a point every 2 seconds?

Example Two: Calculate the charge if a current of 15 A is flowing for 5 seconds.

Example Three: How much time does it take for 25 C of charge to flow past a given point at 5 A?

An ammeter is a device which measures electric current.

ELECTRIC CURRENT If the current flows in one direction only (from negative to positive), it is called direct current (DC). If the current flows in one direction and then the other direction (alternates direction of flow) it is called alternating current (AC).

ELECTRIC POTENTIAL (VOLTAGE) Electric potential is related to the amount of energy given to the electrons flowing in the circuit (electrons from a cell, such as a 1. 5 V battery, have 1. 5 volts of energy whereas electrons from the wall outlet have 110 volts of energy). Electric potential is measured in Volts (V). A voltmeter measures electric potential.