Final answer:
A particle with a charge and mass exhibits a circular path when traveling through a uniform magnetic field due to the Lorentz force. The direction of deflection indicates the sign of the charge. The radius of the path can be calculated, and the speed of the particle remains constant within the magnetic field.Option A is the correct answer.
Step-by-step explanation:
The particle you've described is most affected by a uniform magnetic field when we consider classical physics scenarios. If a particle with charge q, mass m, and kinetic energy T travels in a magnetic field, it may be deflected into a circular path if the magnetic field is perpendicular to the particle's velocity. This deflection is due to the Lorentz force acting on the moving charge.
(a) The initial deflection direction of the particle can determine the sign of its charge. According to the right-hand rule, if a positively charged particle moving downward is deflected north in a uniform magnetic field directed from east to west, it means the charge is indeed positive. A negatively charged particle would have been deflected south under the same conditions.
(b) The radius of the circular path r can be calculated using the formula r = mv / (qB). Given the speed v, magnetic field B, and charge-to-mass ratio q/m, you can solve for r.
(c) As long as the particle remains within the uniform magnetic field and follows a circular path, its speed remains constant because the magnetic force does only directional work and doesn't change the kinetic energy of the particle. Thus, the speed after any time spent in the field will be the same as the initial speed, assuming no other forces are acting.