In a particle accelerator, you accelerate an electron. Afterwards, you measure it's energy to be 350 keV. Tell my why you can't find the speed from this energy using your knowledge of classical mechanics.
In order to see what the problem is, I will attempt to find this speed. 350keV=5.6110-14 J Ek=1/2 * mv2 => v=sqrt(2Ek/m) By plugging in numbers, we find that the velocity of the electron, v=3.51108. This velocity is bigger then the speed of light c=3108, and it is a known fact that nothing can travel faster than light. This means that relativistic effects must've taken place, which prevented the particle from reaching the speed of light, but allowed it to have such a high energy.
CP
Related Physics A Level answers
All answers ▸In still air an aircraft flies at 200 m/s . The aircraft is heading due north in still air when it flies into a steady wind of 50 m/s blowing from the west. Calculate the magnitude and direction of the resultant velocity?
What is an equipotential in an electric/gravitational field?
3 resistors, R1, R2 and R3 are attached in parallel across a 6V cell with resistances 3, 4 and 5 Ohms respectively. Calculate the current across each resistor.
A linear accelerator (LINAC) is used to accelerate protons at CERN before they are injected into the Large Hadron Collider. Explain with the aid of a diagram how the proton is accelerated by the LINAC.