7. a block of copper of unknown mass has an initial temperature of 65.4oc. the copper is immersed in a beaker containing 95.7g of water at 22.7oc. when the two substances reach thermal equilibrium, the final temperature is 24.2oc. what is the mass of the copper block?

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,?