How does bomb kill tank?

[Masherbrum]

tbh the shockwave rips the armor apart, i seen photos of the aftermath of a B-17 carpet bombing in normandy not only were tanks flipped, but alot were ripped apart, another thing that cuases it is the concussion would sometimes set off round inside the tank.

TBH, the concussion (from even a 100lb bomb) will scramble brains/bodies first, foremost and easiest.

[W7LPNRICK]

500 & 1000 lb'rs treat tanks like beer cans. Many many bodies are discovered during war aftermath with no outward injuries. Only signs of death are pale skin (No vitals) and maybe blood in their ears or eyes. Killed by pure shock wave energy.

[Cthulhu]

tbh the shockwave rips the armor apart, i seen photos of the aftermath of a B-17 carpet bombing in normandy not only were tanks flipped, but alot were ripped apart, another thing that cuases it is the concussion would sometimes set off round inside the tank.

If you're referring to the picture I think you are, the tank in question was a Tiger I, and it was actually struck directly by a 500lb bomb.

It's true that large blasts can toss big armor around like toys, but provided they're buttoned up, the kill mechanism is most likely blunt trauma due to rapid acceleration of the personnel inside. I can check with a buddy of mine who does Lethality Analysis, but I'm pretty sure that the armor of an MBT is stout enough to handle some righteous over-pressures, so provided they're buttoned up, a big exterior HE blast (short of a direct/or near-direct hit) should have minimal direct effect on the crew. When a bomb explodes nearby, the energy of the blast is temporarily stored as strain energy in the tank's armor, and what little bit reaches the crew is due to displacement of air INSIDE the tank due to the deflection of the armor. Provided the armor itself doesn't fail, it's not really a big deal.

Also, provided the tank's ammo, specifically the primer/safe-arm device, is properly designed, there's no way that shock/vibration (what you call concussion) is going to detonate modern explosives. It takes extremely high energy levels (read that HIGH HEAT) to do the job.

Not totally relevant to the discussion, but here's some Eye Candy:

We designed LOSAT here in Dallas:
http://www.youtube.com/watch?v=ho_VHOjzMX0&feature=related

http://www.youtube.com/watch?v=ULRsLR1i1yU&feature=related

http://www.youtube.com/watch?v=DwixhQI-r5w&NR=1

Our buddies in Orlando created Javelin:
http://www.youtube.com/watch?v=dH4PkOhrSn0&feature=related

[RTHolmes]

I imagine modern composite armour is designed to disrupt the propagation of the shock wave through to the interior of the tank so the effects would be much reduced these days, but the solid chunks of steel used in WWII would transmit the energy pretty well I'm guessing. I can see delamination being a problem for modern armour though under these conditions maybe

[Lusche]

In 1942, the Luftwaffe conducted a series of tests to evaluate the efficiency of large bombs against tanks. 550lbs SC-250 were used against T-34's, M-4 Sherman and Mark IV Churchills.
Results: Churchill was the weakest tank, it's hull was ruptured by one SC-250 detonating at a distance if 5m. Both the T-34 and M-4 hulls did survive an explosion at only 3m, but test animals inside the tanks were killed by overpressure and the T-34's fuel ignited.