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An electron and a proton have the same kinetic energy upon entering a region of constant magnetic field and their velocity vectors are perpendicular to the magnetic field. suppose the magnetic field is strong enough to allow the particles to circle in the field. note: you'll need to look up the masses for an electron and proton. 1) what is the ratio of the radii of their circular paths rp/re?

This is for my 8th grade science class, i really don’t understand. can someone me? , lol.

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value