Castle Electricity Section 2

Castle Electricity Section 2

• Resistors in a circuit maintain equal inflow and outflow rates of charge. The charge isn't used up passing through the resistor.
• Bulbs and resistors impede charge flow. Resistors are added to circuits because they are more reliable than bulbs; they don't heat up or burn out as easily.
• Starbursts and arrowtails indicate how brightness and flow rate change with the number of bulbs in a circuit. Fewer bulbs = brighter = greater flow rate. More bulbs = dimmer = less flow rate.
• Resistors are circuit components made of materials that regulate/limit the flow of electrical current. These materials are intermediate between conductors and insulators.
• Resistance is the property of a resistor that specifies how well it resists the flow of charge. Low resistance allows charge to flow easily. High resistance impedes charge flow. Resistance is measured in ohms (Ω).
• Current is the flow rate of charge, measured in amperes (A). Flow rate is not the same as speed; flow rate is the net amount of charge that passes in a specific time, while speed is distance travelled in a specific time.

Lighting of Long vs. Round Bulbs

• Long bulbs have more resistance than round bulbs. This means the long bulb did not light as quickly as the round bulb.

Filament, Wires, and Connecting Wires in Bulbs

• Filaments are the thinnest wires.
• Wires in the bulb are thicker than filaments, but thinner than connecting wires.
• Connecting wires are the thickest wires.
• The filament in the round bulb is thicker than the filament in the long bulb.
• The most difficult flow rate is in the long bulb’s filaments.
• The least difficult flow rate is in the connecting wires.

Series vs. Parallel Circuits

• Series Circuits: Bulbs/resistors are arranged in a single line. The charge must pass through each component in the circuit. Adding more components in series increases the total resistance. This makes it more difficult for charge to flow.
• Parallel Circuits: Bulbs/resistors are connected side-by-side. The charge has multiple pathways to travel. Adding more components in parallel decreases the total resistance, making it easier for charge to flow.

Review: Series Circuits

• More resistors in series = longer single resistance (4 straws taped end to end).
• Greater resistance for charge flow.
• All moving charges pass through every resistor in the series.
• Every part of the charge is resisted every time it passes through the resistor.
• More resistors in series = single longer resistor = harder flow rate.

Review: Parallel Circuits

• More resistors in parallel have a thicker single resistance (4 straws taped side-by-side).
• Less resistance to charge flow.
• The moving charge is split into parts.
• Each part will pass through only one resistor; movement is only resisted once.
• More resistors in parallel = single thicker resistor = easier flow rate.