LEDs

What does LED stand for?

• Laser Emitting Diode

• Light Energy Diode

• Luminous Electric Device

• Light Emitting Diode

What is the typical wavelength range visible to humans?

• 500 to 800 nanometers

• 300 to 600 nanometers

• 400 to 700 nanometers

• 600 to 900 nanometers

What type of light does a TV remote's LED emit?

• Visible Red

• Infrared

• Ultraviolet

• Blue

What is the purpose of the flat edge on an LED?

• To improve light emission

• For aesthetic purposes

• To indicate the anode side

• To indicate the cathode side

What happens when a voltage is applied across an LED?

• It produces a magnetic field

• It produces light

• It produces heat

• It produces sound

What is the function of a resistor in an LED circuit?

• To decrease the voltage

• To increase the voltage

• To store electrical energy

• To protect the LED by limiting current

What does the color of an LED depend on?

• The color of the case

• The wavelength of the photon it emits

• The shape of the LED

• The amount of voltage applied

What are SMD LEDs used for?

• In light bulbs for compact designs

• In remote controls only

• For high power applications only

• For outdoor lighting only

How can the brightness of an LED be controlled?

• By changing its color

• By using multiple LEDs

• By varying the current

• By using a larger battery

What is the minimum voltage required for a red LED to start conducting?

• 1.1 volts

• 2 volts

• 1.7 volts

• 0.5 to 0.7 volts