Table of Content 4.1 Thermionic Emission and Cathode Ray 4.2 Carthode Ray Oscilloscope 4.3 Semiconductor 4.4 Semiconductor Diode 4.5 Trasistor 4.6 Logic Gate

Cathode Ray Oscilloscope

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1) The diagram shows a trace on a cathode ray oscilloscope (CRO). Which of the following statement is true about the signal displayed and the setting of the CRO?
1. This is an alternating current.
2. The time base is off
3. The voltage is 2V
 I and II only I and III only II and III only I, II and III

2) The diagram shows a trace on an oscilloscope. The Y-gain control of the cathode-ray oscilloscope is set to 5V/div. What is the root mean square voltage of the signal?

 5.15V 7.07V 10.00V 20.00V

3) The diagram shows a trace on an oscilloscope. The time-base of cathode-ray oscilloscope is set to 5 ms/div. What is the frequency of the signal?

 25Hz 50Hz 100Hz Can't be determined!

4) Figure above shows a waveform of an alternating current on the screen of a cathode ray oscilloscope. The Y-gain control is set to 5V/div. Find the peak voltage of the alternating current.

 3V 6V 15V 30V

5) Diagram above shows the internal structure of a cathode ray oscilloscope. Name the parts Q, R and S in the electron gun.

 Q R S Focusing Anode Control Grid Accelerating Anode Control Grid Accelerating Anode Focusing Anode Control Grid Focusing Anode Accelerating Anode Cathode Focusing Anode Accelerating Anode

6) Which part of the cathode ray oscilloscope controls the brightness of the light spot on the screen?

 Control grid Focusing anode Deflecting plates Accelerating anode

7) Figure above shows a sonar signal recorded on a cathode ray oscilloscope (CRO) when it is emitted by a ship and reflected back by the seabed. Given that the time base of the CRO is set to 100ms/div, find the depth of the sea beneath the ship. (The speed of sonar wave in sea is 1500ms-1)

 375m 500m 750m 1000m