7.2 FLOW OF ELECTRIC CURRENT IN SERIES AND PARALLEL CIRCUIT

7.2 FLOW OF ELECTRIC CURRENT IN SERIES AND PARALLEL CIRCUIT

by KASMAWATI Moe

Static Electricity

• Definition:

• Static electricity is the build-up of an electrical charge on the surface of an object.

• The reason that it's actually called static electricity is because the charges stay in one area for some time and don't flow or move to a different area.

• Rubbing the balloon on hair or even a carpet will allow it to stick to walls and even hair!

Circuit Symbols

• Battery

• Bulb

• Switch

• Resistor

Series circuits

• All elements in the circuit are in one loop

• Every electron flow through every element

• If one bulb burned out, the rest would also go out

​​Series Circuits Rules

​1. the current in the circuit is constant.

Current in all parts of the circuit is the same.

Parallel circuits

• There are several pathways or loops through the circuit

• Electrons flow through just one of those pathways

• If one bulb burned out, the rest of the bulbs would still glow

Ohm's Law - V=IR

• Shows the relationship between current, voltage, and resistance

• V is for VOLTAGE (volts)

• I is for CURRENT (amps)

• R is for RESISTANCE (ohms)

Voltage (V)

• Comes from the battery or another voltage source

• The "push" that moves electrons around the circuit

• Think of it like a water pump - without the pump, the water would just sit in the pipe and not move anywhere

Current (I)

• Electrons in the circuit flowing or moving around the circuit

• Measured in amps

• When electrons move faster, the current is greater

• Like the water flowing through a pipe

Resistance (R)

• Makes it harder for electrons to flow through the circuit

• Measured in Ohms

• Kind of like friction or sand that slows the water in the pipe down

Ohm's Law

Example 3

• How much current would flow through a circuit with 25 ohms of resistance and 100 volt battery?

• 
  

• 
  

Multiple Choice

As resistors are added in series to a circuit, the total resistance will...

• increase
• decrease
• stay the same

Multiple Choice

In a parallel circuit which of the following is the same value throughout the circuit?

• Voltage
• Current
• Resistance
• Charge

Multiple Choice

As the resistance of a circuit increases, the current will...

• increase
• decrease
• stay the same

Multiple Choice

What kind of circuit is this?

• series
• parallel

Multiple Choice

This is an example of a ______ circuit

• Series
• Parallel
• Open
• Dihexihedral

Multiple Choice

What is the type of circuit that stops working when one bulb goes out?

• A broken circuit
• Parallel Circuit
• Series Circuit
• A metal circuit

Multiple Choice

In a parallel circuit if one of the light bulbs burns out the rest _________.

• stop the flow of electricity
•  can still light up
•  will go out
• of the light bulbs burn out also

Multiple Choice

what kind of circuit is this?

• parallel
• series
• chris barton
• open

Multiple Choice

What is the resistance of a lightbulb that experiences 9 Volts and 3 amps of current?

• 1/3 ohms

• 3 ohms

• 27 ohms

• 9 ohms

Multiple Choice

What is the current in a circuit with 6 ohms of resistance and a battery containing 24 Volts?

• 1/4 A

• 144 A

• 4 A

• 0.4 A

Multiple Choice

Which circuit is an example of a Parallel circuit?

Multiple Choice

Which circuit is an example of a series circuit?

Multiple Choice

How do you measure current?

• scale

• meter stick

• ammeter

• voltmeter

• potentiometer

Multiple Choice

How do you place an ammeter in a circuit?

• parallel to the component

• in series with the component

Multiple Choice

How do you measure the potential difference?

• scale

• meter stick

• ammeter

• voltmeter

• potentiometer

Multiple Choice

How do you place a voltmeter in a circuit?

• parallel to the component

• in series with the component

Multiple Choice

Calculate the effective resistance of three resistors in series if they have the following values: 1.2 kΩ, 5.6 kΩ and 7.1 kΩ.

• $$6800\ \Omega$$

• $$12700\ \Omega$$

• $$13900\ \Omega$$

Multiple Choice

What did that slide mean?

• current is the same across each component in parallel

• voltage is the same across each component in parallel

• resistance is the same across each component in parallel

Multiple Choice

Calculate the effective resistance of two resistors in parallel if they have resistance values of 1.2 kΩ and 4.8 kΩ.

• $$6.0\ k\Omega$$

• $$1.04\ k\Omega$$

• $$0.96\ k\Omega$$