A particle spiraling in a magnetic field

A particle with specific charge α:=qm=108 C/kg \alpha:= \frac{q}{m}=10^{8} \textrm{ C/kg} enters a bubble chamber where its path can be observed. A magnetic field of induction B=102T B=10^{-2} \textrm{T} is perpendicular to the particle's velocity. The particle experiences a viscous drag force which is approximately proportional to its velocity, that is Fdrag=kv. \vec{F}_{drag}=- k \vec{v}. As a consequence of this force, the particle spirals inward. It is observed that after two full rotations the radius of curvature decreases by 2%2 \% . Then the magnetic field is switched off and the particle travels L=30cmL=30 \textrm{cm} before coming to a stop. What was the particle's velocity in m/s right before entering the chamber?

×

Problem Loading...

Note Loading...

Set Loading...