What is a unit of explosive power?

Answer 1

• Explosive power is usually expressed relative to its equalent in TNT. So you could say a particular nulcear explosion was equivalent to 8 megatons of TNT. You can also express the energy of an explosion in calories or any equivalent energy unit. One kiloton of TNT is approimately 10^12 calories.
• It depends on whether you're a military engineer or a commercial blaster. Military engineers rely on the Relative Effectiveness rating of the product--how much more powerful than TNT an explosive is. Commercial blasters also look at the detonation velocity. Mining blasters look at price too--if Product A is half as effective but costs one-third as much as Product B, they'll just drill a bigger hole and pack in twice as much Product A. Building demolition people think more in terms of time--the fewer times you have to walk out of the building to get more explosives, the quicker you can do the job and the quicker you get paid, so a more powerful explosive that will let you get more charges out of 100 pounds of product would be worth a premium.