On a hot day, yon are in a sealed, insulated room. the room contains a refrigerator, operated by an electric motor. the motor does work at the rate of 438 w when it is running. the refrigerator removes heat from the food storage space at a rate of 450 w when the motor is running. in an effort to cool the room, you open the refrigerator door and let the motor run continuously. at what net rate is heat added to (+) or subtracted from (−) the room and all of its contents?

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,?