[Legacy] Introductory Electronics
16 questions· page 1 of 2
A student suggests four conditions for the production of a continuous flow of electrons from a metal filament.
- The filament is hot.
- A high-pressure gas is present.
- A high positive electrical potential is present.
- A strong magnetic field is present.
Which of the four conditions are needed?
Options
A 1 and 4
B 2 and 3
C 1 and 3
D 2 and 4
Which particles are emitted by a hot metal filament?
Options
A alpha-particles
B electrons
C neutrons
D protons
Which particles are emitted by a hot metal filament?
Options
A alpha-particles
B electrons
C neutrons
D protons
The diagram represents thermionic emission from a metal filament.
The particles are attracted by a charged plate.
Which row shows the charge on the plate, and the temperature of the metal filament?
Options
| charge on plate | temperature of metal filament | |
|---|---|---|
| A | negative | high |
| B | negative | low |
| C | positive | high |
| D | positive | low |
The diagram shows a cathode-ray tube. The dotted line shows the path of a beam of electrons. The beam hits the screen at point X and produces a bright spot. P and Q are horizontal plates on each side of the beam.
Which change will move the bright spot to a different position on the screen?
Options
A Apply a voltage between metal plates P and Q.
B Decrease the positive voltage of the anode.
C Increase the positive voltage of the anode.
D Increase the voltage between the terminals of the cathode.
The table gives the colour code used for marking resistors.
| black | brown | red | orange | yellow | green | blue | violet |
|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
What is the resistance of the resistor in the diagram?
Options
A
B
C
D
Which particles are emitted by the hot filament of a cathode-ray oscilloscope (c.r.o.) and which type of field is used to accelerate them?
Options
| particles | type of field | |
|---|---|---|
| A | electrons | electric |
| B | electrons | magnetic |
| C | protons | electric |
| D | protons | magnetic |
Which particles are emitted by the hot filament of a cathode-ray oscilloscope (c.r.o.) and which type of field is used to accelerate them?
Options
| particles | type of field | |
|---|---|---|
| A | electrons | electric |
| B | electrons | magnetic |
| C | protons | electric |
| D | protons | magnetic |
A resistor is marked with three coloured bands.
| black | brown | red | orange | yellow | green | blue | violet |
|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
Using the key provided, what is the resistance of the resistor?
Options
A
B
C
D
The diagram shows part of a cathode-ray oscilloscope.
Which particles are emitted by the cathode?
Options
A electrons
B helium nuclei
C neutrons
D protons