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 ▸Show that the radius of an orbit may be expressed as follows: R^3=((GM)/4*pi^2)T^2
what depends if the universe is expanding or not
Explain, using appropriate laws of motion, why the air exerts a force on the engine in the forward direction.
Two railway trucks of masses m and 3m move towards each other in opposite directions with speeds 2v and v respectively. These trucks collide and stick together. What is the speed of the trucks after the collision?