Day 06 - Ohm's Law Review

Today we're covering Worksheet A, which will be similar to yesterday's TinkerCad work but with some numbers to record and puzzle out. Take your time, record your data carefully, and make sure you understand what it is you are writing.

The directions for the worksheet can be found in the digital version above, but I'll reprint them for you below so you can also take advantage of the hyperlink embedded in the instructions:

Purpose:

The purpose of this activity is to determine the mathematical relationship between battery voltage (∆V), current (I), and resistance (R) for a simple circuit.

Getting Ready:

Navigate to the DC Circuit Builder Interactive at The Physics Classroom:
www.physicsclassroom.com => Physics Interactives => Electric Circuits => DC Circuit Builder
or
DC Circuit Builder.

Resize the Interactive using the small handles in the bottom right corner or go full-screen by tapping the icon in the upper left corner. Observe the tools in the Toolbox region below the red Workspace area. Experiment with these tools to create a circuit. Simply select a circuit component and tap on the workspace to add it to the circuit; add wires, resistors, bulbs and ammeters as desired. Tap on a component in the workspace to remove it.

Build, Measure, Analyze

1. Clear your Workspace by clicking on all components; only the battery should remain. Using the tools in the Toolbox area, create a simple circuit consisting of a battery, a bulb, an ammeter (for measuring current in amps), and wires.
2. Select the Modify icon (shown at right); observe that the magnifying glass appears over the battery. This indicates that you can change the voltage of the battery. Use the arrows to lower the battery voltage to 6.0 Volts.
3. The ammeter reads the current (I) in amps. Record the ammeter reading in Table 1.
4. Repeat steps 2 and 3 until Table 1 is complete. Use the Modify icon to increase the voltage of the battery (∆V) for each of these trials.
5. Tap the Modify icon and then tap on the light bulb. The resistance (R) of the light bulb is displayed. Record this resistance value above Table 1. Then double the value of the light bulb's resistance and repeat the experiment for Table 2. Complete Table 3 with a resistance value that is three times as large.

coil

a layered loop of conductive material (such as copper); current through this loop will produce a magnetic field

commutator

a cylinder with a break in it such that as it spins it keeps breaking the circuit for a moment to allow a reversal of current

current

in electronics, it is the movement of electrons through a circuit; this movement can be direct (flow) or alternating (vibration)

electromagnetism

the physics invovled with the flow of electrons and their magnetic fields

magnetic field

the accumulation of force from millions of electrons aligned in the same direction, making the substance behave like an ionic element