Electron Deflection in Magnetic Field

An electron, moving along the x axis with an initial energy of 100eV , enters a region of magnetic field

→

B

=(1.5×10−3T)

^

k

at S (See figure). The field extends between x=0 and x=2 cm . The electron is detected at the point Q on a screen placed 8 cm away from the point S. The distance d between P and Q (on the screen) is: (electron’s charge 1.6×10−19C , mass of electron 9.1×10−31kg)