Ohm’s Law
Ohm’s Law
Measuring Current Current is measured in unit amps (A) In a series circuit, current is the same at all the points In a parallel circuit, current is shared between all the points
What is the current? SERIES CIRCUIT PARALLEL CIRCUIT 3A 3A 4A 1A 4A 1A
Measuring Voltage Voltage – the electrical push that a cell/battery gives to the current Voltage is also known as Potential Difference Voltage is measured in unit volts (V)
Measuring Voltage 3V 1.5V 3V In a series circuit, voltage is shared between all the points In a parallel circuit, voltage is the same at all the points
What is the current and voltage? Series Same Shared Parallel
What is the current and voltage?
Measuring Resistance Resistance – slows down current, adding components to a circuit increases resistance Resistance is measured in unit ohms (Ω) More resistance = Less current = Less light In a series circuit, add all resistors to get total
Electrical Power
What is the current?
What is the current?
What is the current?
How much voltage gives 5 amps of current through a 3 Ω light bulb? I = V/R V = (5A) (3Ω) V = 15V
How much current flows in a circuit with a 1 How much current flows in a circuit with a 1.5 volt battery and three 1 ohm resistances (bulbs) in series? I = V/R I = (1.5V) / (3Ω) I = .5A
What is the voltage drop across each resistor in the circuit? In a series circuit, voltage is shared between all the points 9V/3 = 3V
A light bulb with a resistance of 1. 5Ω is connected to a 1 A light bulb with a resistance of 1.5Ω is connected to a 1.5V battery in the circuit. Calculate the power used by the light bulb? P = IV I = V/R I = (1.5V) ÷ (1.5Ω) I = 1A P = (1A) (1.5V) P = 1.5 W