Which of the following must be happening if an object is in uniform circular motion?
O A. The object must be moving in a straight line.
O B. The object's velocity must be changing.
O C. The object's speed must be changing,
O D. The object's centripetal acceleration must be changing,

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,?