Quiz on Internal Impedance of Instruments

What is the internal resistance of an ideal voltmeter?

• Infinite

• High

• Low

• Zero

How is a real voltmeter represented in an equivalent circuit?

• As an ideal meter with zero resistance

• As an ideal meter with internal resistance

• As a capacitor

• As an inductor

What should be the internal resistance of a good ammeter?

• Low

• Infinite

• Zero

• High

What happens to the output voltage of a real voltage source when a load is connected?

• It remains the same

• It increases

• It becomes zero

• It decreases

Which instrument is used to measure the internal resistance of an analog ammeter?

• Resistance substitution box

• Digital voltmeter

• Analog voltmeter

• Oscilloscope

What is the purpose of using a resistor in series with an analog ammeter?

• To decrease the voltage

• To protect it from excessive current

• To measure resistance

• To increase the current

What is the effect of a voltmeter on a low impedance circuit?

• No effect

• Significant effect

• Increases impedance

• Decreases impedance

What should be the load resistance to measure the internal resistance of a waveform generator?

• Zero

• High enough to see no voltage change

• Low enough to see the voltage change

• Equal to the internal resistance

What is the expected internal resistance of an oscilloscope?

• Zero

• Infinite

• High

• Low