An alpha particle (4He2+^{4}\text{He}^{2+}4He2+) enters a uniform magnetic field of flux density 0.75 T0.75\text{ T}0.75 T and is deflected into a circular path of radius 25 cm.
What is the momentum of the alpha particle?
3.0×10−20 kg m s−13.0 \times 10^{-20}\text{ kg m s}^{-1}3.0×10−20 kg m s−1
6.0×10−20 kg m s−16.0 \times 10^{-20}\text{ kg m s}^{-1}6.0×10−20 kg m s−1
3.0×10−18 kg m s−13.0 \times 10^{-18}\text{ kg m s}^{-1}3.0×10−18 kg m s−1
6.0×10−18 kg m s−16.0 \times 10^{-18}\text{ kg m s}^{-1}6.0×10−18 kg m s−1
