Hey so help me out here please. This is an Edexcel Physics A2 question (I'm doing A Levels). I really don't know if this will make sense at all lol So there are cyclotrons- where the mass of the particle must me constant, that is, the limitation of the cyclotron is that it does not take into consideration the relativistic effects on mass, right? Then there's the synchrocyclotron, which is basically a modifies version of the cyclotron, and it DOES take into consideration the relativistic effects on mass, in that it alters the frequency of the applied p.d according to the changing frequency of the particle which is now close to the speed of light, right? i.e the frequency of the voltage is changed. But my question is that my teacher talked about something that I haven't been able to find on Google- he talked about a SYNCHRONISED CYCLOTRON. And this is what he said: At greater speed, that is when speed of the particle approaches the speed of light, according to the theory of relativity, the mass increase. So frequency of the particle decreases. But to keep on accelerating the particle, the frequency of revolution of the particle must be equal to the frequency of the a.c voltage, so the frequency of the particle can just be kept constant by increasing the magnetic field. But if the frequency AND the magnetic field were kept constant, then wouldn't it just be a synchrotron? If tl;dr- is there such a thing as a SYNCHRONISED CYCLOTRON? Which does not change the frequesncy of the a.c voltage with some clever circuitry, as in the synchrocyclotron, but which takes into account the relativistic effects on mass, unlike the classical cyclotron? Thank you so much. I've googled about this a lot and have found NOTHING on the synchronised cylotrons my teacher talked about, and this is driving me crazy. Please respond, K bye.