two scientists are experimenting with pure samples of isotope x, a highly radioactive substance. the first scientist has a sample with a mass of 20 grams. he measures a half-life of 232 seconds. the second scientist has a sample of the same substance with a mass of 80 grams. what is the half-life that she is most likely to measure?
a. 58 seconds
b. 232 seconds
c. 464 seconds
d. 928 seconds

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,?