A deuteron particle (the nucleus of an isotope of hydrogen consisting of one proton and one neutron and having a mass of 3.34×10^-27 kg) moving horizontally enters a uniform, vertical, 0.660T magnetic field and follows a circular arc of radius 57.0 cm. How fast was this deuteron moving just before it entered the magnetic field ? in m/s How fast was this deuteron moving just after it came out of the field? What would be the radius of the arc followed by a proton that entered the field with the same velocity as the deuteron?