A 2.0 MF capacitor is charged using a 0.40V from a cell and voltage divider circuit. it is then discharged quickly through a ballistic galvanometer and meter gives a maximum deflation of 6.4cm what is the sensitivity of the meter

During the experiment if you could triple the breakaway magnetic force with all other quantities left unchanged, what is the new value for the critical velocity if it was v0 (initial velocity), initially? (b) now if you halved the radius with all other quantities left unchanged, what is the new critical velocity if it was v0 (initial velocity), initially? (c) if during the experiment, critical velocity quadrupled with all other quantities left unchanged, what is the new breakaway force if its magnitude was initially f0,?