Electrons are accelerated through a potential difference of 300 V. What is their final de Broglie wavelength?
The kinetic energy of the electron will be equal to the energy what the electric field gives to it.1/2mv2=VQFrom thisv=sqrt(2VQ/m)
De Broglie wavelength:lambda=h/p=h/(mv) We know that h is the planck constant, V=300V Q is the charge of an electron and m is the mass of it.
If we substitute these into the equations above we get lambda=710-11m
CB
Related Physics A Level answers
All answers ▸How does the strong nuclear force between two nucleons varies with separation of the nucleons. Please detail the range over which the force acts.
A cricketer throws a ball vertically upwards so that the ball leaves his hands at a speed of 25 m/s. Calculate the maximum height reached by the ball, the time taken to reach max. height, and the speed of the ball when it is at 50% max. height.
Explain why a transformer is used in electrical power lines.
Explain, using appropriate laws of motion, why the air exerts a force on the engine in the forward direction.