Monday, March 12, 2018

Circuit Wizardy question

Q1) Are the kids going to be expected to do all three measurements (voltage, resistance and current) to prove ohm’s law? With the low voltage battery pack and a small value resistor, the resistance of the multimeter is not negligible so it affects the current measurement.

A1) Students will not be asked to make all three measurements to verify Ohm's law. They will be asked to make one of the three measurements with respect to the circuit they built in section 3 of the test (see, for example the sample problem in the event description). There will be an allowed margin of error of 10% to account for differences in components and battery strength.

Q2) Will the kids get points off if they round up their calculations (if voltage measures 2.7 can they round to 3)?
A2) Students should not round up to whole numbers. The questions will specify the accuracy. For example, they may be asked to report the answer to the nearest tenth of a volt or mA. All answers must include units.

Q3) Can you send an example of how the kids are expected to use the capacities in a circuit?

A3) Students should know the function of a capacitor and how they behave. For example, a google search should find examples of circuits where a capacitor and resistor are used to allow an LED to slowly fade out.