13. IE ••• The same type of incident particle is used for two endoergic reactions. In one reaction, the mass of the target nucleus is 15 times that of the incident particle, and in the other reaction, it is 20 times the incident particle’s mass. The Q value of the first reaction is known to be three times that of the second.

(a) Compared with the second reaction, the first reaction has (1) greater,

(2) the same amount of, (3) less minimum threshold energy.

(b) Prove your answer to part

(a) by calculating the ratio of the minimum threshold energy for the first reaction to that for the second reaction.