Question
Write down the difference between vacuum tube (valve) and semiconductors.
✓
Answer
| Vacuum tube | Semiconductor | |
| 1 | Devices and instruments made of vacuum tube are bulky in size. | Devices/instruments made of semiconductor are comparatively small (compact) in size. |
| 2 | They consume high power and operate at high voltages $(\sim 100 V$.) | They consume low power and operate at low voltages. |
| 3 | They have limited life and low reliability. | They have long life and high reliability. |
| 4 | Controlled flow of electrons is obtained by varying the voltage between its different electrodes. | Controlled flow of electrons can be obtained by small applied voltage (or other simple excitations like light/ heat.) |
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