This is a true story: a few years ago i had a dead tree removed from the front lawn. and as the operator was grinding down the stump, he severed the natural gas line that led to my house. the operator abandoned the site without informing the gas company for me- i was still at work. natural gas has is denser than air and had flowed into the ground and basement, where any small spark would have ignited the gas. the gas line was open for 4 hours before the gas company turned off the supply.
a) how much natural gas had flowed into the ground and basement on the day the line was cut? the gas line is 0.5" diameter pressurized to 0.5 psig
b) natural gas has an energy content of 39 mj/m^3 compare this to a stick of dynamite that has 2.1 mj how many sticks of dynamite were essentially in my basement? (equivalent)