Q value is the emitted part of an energy ledger. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Thirty minus twenty-four releases six

Initial energy 30 joules minus final energy 24 joules leaves emitted energy 6 joules.

Q=3024=6 JQ=30 - 24=6\ \mathrm{J}
Q-value closure scanThe emitted energy is checked as initial minus final.initial=30 Jfinal=24 Jemitted=6 J

Fifty minus thirty-five releases fifteen

Initial energy 50 joules minus final energy 35 joules leaves emitted energy 15 joules.

Q=5035=15 JQ=50 - 35=15\ \mathrm{J}
Q-value closure scanThe emitted energy is checked as initial minus final.initial=50 Jfinal=35 Jemitted=15 J

Eighteen minus eleven releases seven

Initial energy 18 joules minus final energy 11 joules leaves emitted energy 7 joules.

Q=1811=7 JQ=18 - 11=7\ \mathrm{J}
Q-value closure scanThe emitted energy is checked as initial minus final.initial=18 Jfinal=11 Jemitted=7 J