Oramac
Regular Member
A car going just 4 MPH has more energy than a bullet. Sounds kinda crazy, but I got the math to back it up. Pretty interesting perspective when you consider that people are afraid of guns, but don't think twice about getting in a car and going 90.
Math (hopefully my formatting carries over):
“A car traveling at just 4 MPH has more energy than a bullet”
E = ½ (mv[sup]2[/sup])
E = energy
M = Mass
V = Velocity
We assume a car weighing 3000 pounds, or 1360.777 kilograms. 4 MPH = 1.787 m/s
E[sub](car)[/sub] = ½ (1360.777)(1.787[sup]2[/sup])
E[sub](car)[/sub] = ½ (1360.777)(3.193)
E[sub](car)[/sub] = ½ (4344.960)
E[sub](car)[/sub] = 2172.48 Joules
Assume: 9mm 115 grain bullet at 1190 fps = .0074518 kg @ 362.712 m/s
E[sub](9mm)[/sub] = ½ (.0074518)(362.712[sup]2[/sup])
E[sub](9mm)[/sub] = ½ (.0074518)(131559.99)
E[sub](9mm)[/sub] = ½ (980.3587)
E[sub](9mm)[/sub] = 490.179 Joules
Assume: .223 round from AR15: 55 grain @ 3240 fps = .003563 kg @ 987.552 m/s
E[sub](223)[/sub] = ½ (.003563)(987.552[sup]2[/sup])
E[sub](223)[/sub] = ½ (.003563)(975258.952)
E[sub](223)[/sub] = ½ (3474.847)
E[sub](223)[/sub] = 1737.423 Joules
Assume: .50BMG sniper rifle: 750 grain @ 2700 fps = .048599 kg @ 822.960 m/s
E[sub](50)[/sub] = ½ (.048599)(822.960[sup]2[/sup])
E[sub](50)[/sub] = ½ (.048599)(677263.1616)
E[sub](50)[/sub] = ½ (32914.312)
E[sub](50)[/sub] = 16457.156 Joules
So, a .50 caliber rifle has more energy than a car, right? WRONG! Remember, the car in our example is going just FOUR miles per hour. Let’s see what a car going 50 miles per hour has.
Assume: 3000 pound car @ 50 MPH = 1360.777 kg @ 22.352 m/s
E[sub](car@50)[/sub] = ½ (1360.777)(22.352[sup]2[/sup])
E[sub](car@50)[/sub] = ½ (1360.777)(499.611)
E[sub](car@50)[/sub] = ½ (679860.387)
E[sub](car@50)[/sub] = 339930.193 Joules
Very interesting comparison.
Math (hopefully my formatting carries over):
“A car traveling at just 4 MPH has more energy than a bullet”
E = ½ (mv[sup]2[/sup])
E = energy
M = Mass
V = Velocity
We assume a car weighing 3000 pounds, or 1360.777 kilograms. 4 MPH = 1.787 m/s
E[sub](car)[/sub] = ½ (1360.777)(1.787[sup]2[/sup])
E[sub](car)[/sub] = ½ (1360.777)(3.193)
E[sub](car)[/sub] = ½ (4344.960)
E[sub](car)[/sub] = 2172.48 Joules
Assume: 9mm 115 grain bullet at 1190 fps = .0074518 kg @ 362.712 m/s
E[sub](9mm)[/sub] = ½ (.0074518)(362.712[sup]2[/sup])
E[sub](9mm)[/sub] = ½ (.0074518)(131559.99)
E[sub](9mm)[/sub] = ½ (980.3587)
E[sub](9mm)[/sub] = 490.179 Joules
Assume: .223 round from AR15: 55 grain @ 3240 fps = .003563 kg @ 987.552 m/s
E[sub](223)[/sub] = ½ (.003563)(987.552[sup]2[/sup])
E[sub](223)[/sub] = ½ (.003563)(975258.952)
E[sub](223)[/sub] = ½ (3474.847)
E[sub](223)[/sub] = 1737.423 Joules
Assume: .50BMG sniper rifle: 750 grain @ 2700 fps = .048599 kg @ 822.960 m/s
E[sub](50)[/sub] = ½ (.048599)(822.960[sup]2[/sup])
E[sub](50)[/sub] = ½ (.048599)(677263.1616)
E[sub](50)[/sub] = ½ (32914.312)
E[sub](50)[/sub] = 16457.156 Joules
So, a .50 caliber rifle has more energy than a car, right? WRONG! Remember, the car in our example is going just FOUR miles per hour. Let’s see what a car going 50 miles per hour has.
Assume: 3000 pound car @ 50 MPH = 1360.777 kg @ 22.352 m/s
E[sub](car@50)[/sub] = ½ (1360.777)(22.352[sup]2[/sup])
E[sub](car@50)[/sub] = ½ (1360.777)(499.611)
E[sub](car@50)[/sub] = ½ (679860.387)
E[sub](car@50)[/sub] = 339930.193 Joules
Very interesting comparison.
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