Viewers of star trek hear of an antimatter drive on the starship enterprise. one possibility for such a futuristic energy source is to store antimatter charged particles in a vacuum chamber, circulating in a magnetic field, and then extract them as needed. antimatter annihilates with normal matter, producing pure energy. what strength (in t) magnetic field is needed to hold antiprotons, moving at 5.70 ✕ 107 m/s in a circular path 2.60 m in radius? antiprotons have the same mass as protons but the opposite (negative) charge. (enter the magnitude.)