Describe one technique you could use to measure the threshold voltage for LEDs.
A sensitive ammeter is placed in series with LED. With the increase in Voltage, measure the potential difference value when it starts conducting. Black-out and shaded vision tube is used to observe the voltage value when visible light is first observed as the voltage is increased.
MP
Related Physics A Level answers
All answers ▸If a star with a radius of 600000km has a surface temperature of 6000K, calculate its luminosity
What happens to the pressure inside a gas-filled ball when the temperature is increased? Explain your answer, stating the assumption made.
Bernard says that a mass executing uniform circular motion is not accelerating as it's speed is not changing. Which parts of his statement are correct and which are false. For those which are false state why they are and give the correct version.
What are the different classifications of sub-atomic particles?