Question

1. It is possible to use the maximum vertical deflection on the oscilloscope screen to find the current. Explain how a numerical value for current may be found. You may choose the value for the resistor. Show how the oscilloscope is to be connected in the circuit diagram below.

(Attempting to draw the circuit diagram, on the top is the resistor and battery is on the bottom)

-------VVVVV--------

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2. How must the value obtained above be adjusted to match a meter reading?

Answer 1

1.

connect the osciloscope across the resistor. Set the osciloscope to maximum vertical deflection. Now you can see the voltage on the vertical scale. If we chose the resistor value to be 1ohm and if we obtain 1mV on screen . Current =V/R =V/1=

1mA.

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2. to match with the meter reading . let voltage from vertical scale is X divisions. Now need to see the scale. lets say V volts/division. So we get voltage =XV volts. NOw current is obtained by dividing this with resistor. XV/R

if we chose R=1 than current =XV Ampere