3. A uniform magnetic field of 45.6 mT points in the z direction, as shown in Fig. 3. At time t = 0 a particle with a charge of -1.60 x 10" C is moving along the positive x-axis, as indicated in the diagram. It has speed of 4.4 x 10 m/s and moves in a circle of radius r = 10 cm. a. What is the direction of the force on the particle when it has the velocity shown in the figure? b. What is the numerical value of the force on the particle? c. What is the momentum of the particle? d. What is the particle's mass? Figure 3: Direction of motion of a negatively charged particle in a uniform magnetic field at some instant of time (problem 3)