Which of the following is not true about LEDs?
Correct answer: C. While connecting to a circuit, the shorter lead of LED is always connected to the positive terminal of the battery
- A. There are two wires (called leads) attached to an LED
- B. While connecting to a circuit, the longer lead of LED is always connected to the positive terminal of the battery
- C. While connecting to a circuit, the shorter lead of LED is always connected to the positive terminal of the battery
- D. LED can be used to detect weak current
Explanation
While connecting to a circuit, the shorter lead of the LED is always connected to the positive terminal of the battery. Explanation: A Light Emitting Diode (LED) is a semiconductor device, which can emit light when an electric current passes through it. To do this, holes from p-type semiconductors recombine with electrons from n-type semiconductors to produce light. The wavelength of the light emitted depends on the bandgap of the semiconductor material. Harder materials with stronger molecular bonds generally have wider band gaps. The LEDs have 2 leads. The lead connected to the positive terminal of the battery is called anode and the lead connected to the negative terminal is called cathode. The longer lead is always connected to the positive terminal because a Thick plate of impure copper is made the positive electrode (anode) and shorter t the negative terminal. LED is also used to detect weak electric currents But the major use of LED (Light Emitting Diodes) is to illuminate objects and even places.
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