Connections in Series and Parallel, Using a Multimeter, Decoding and Measuring Resistors

Connections in Series and Parallel

First example with switch open

In the first example in the picture below when the switch is closed we predicted that all three of the light bulbs would be the same brightness so therefore light bulbs one and two would get dimmer than before and the third light bulb would turn on, but the answer was that nothing happened and light bulb three didn’t turn on because the potential difference between each side of the bulb was zero.  

First example with switch closed

second example with switch open

For the second example when the switch was closed we predicted that both of the light bulbs would get dimmer because of the direction of the flow due to the position of the battery in the circuit, but the answer was that nothing happened and the bulbs stayed the same brightness because the potential difference between each side of the battery was the same making the potential difference 0.  

pictures drawn of examples 1 & 2 and predictions/answers

Using a Multimeter

Series

A circuit was set up in series with two bulbs and two batteries.  Using a multimeter the current and voltage were measured.  After taking measurements it can be seen that in a series circuit the current is the same across the wires bulbs and batteries and that the voltage across the light bulbs adds up to be the voltage across the batteries. 

Parallel

We preformed the same task as in the series circuit for the parallel circuit and measure the current and voltage in the parallel circuit.  After making all the measurements it can be seen that this is the exact opposite of the series circuit.  The voltages are the same everywhere and the currents add up across the bulbs to equal the total current. 

Decoding and Measuring Resistors

Resistors have a code that measures the resistance throughout the resistor.  The equation is AB x 10 ^ C.  We were gives three resistors and found the resistance value that they should be giving.  We tested one of the resistors strength by measuring its resistance with a multimeter.  For that specific resistor we calculated 100 +/- 5 ohms and when we measured it with the multimeter, we got a value of 97 ohms which falls within the uncertainty range of the resistor meaning that this is a reliable resistor/manufacturer.