An observer sees a lightning flash from a distant thunderstorm and 12 seconds later hears the sound. If the ..? temperature of the air is 20°C how far from the storm is the observer? (Assume that light travels instantaneously.)

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,?