After looking online and checking papers I`m not closer to get a useful result. The thing is I find some many different equations and they all give totally different answers. [a] A wall is 3 m high and infinintly long. An explosion of 25 kg TNT is done at a distance of 10 m on the ground. What is the reflected over pressure Pr and the impulse I of the explosion on the wall? Maybe if someone would know of a could source and I`ll try again [/a] 2. Relevant equations Z=R/W1/3 1. P=1772/z3-114/z2+108/Z 2. P=6784(W/R3)+93(W/R3).5 1. gives 66.1 bar? 2. gives 184.3 bar?