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 ▸

What does the double slit experiment tell us about light?


A ball is launched upwards at 30 degrees to horizontal with a velocity of 20 metres per second, how far does it travel before landing? (no air resistance)


Rutherford’s alpha particle scattering experiments gave what evidence about an atom?


Electrons are accelerated through a potential difference of 300 V. What is their final de Broglie wavelength?