Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

So let's say for example I have an object with 5kg of mass.

It explodes with a force of 500N.

The object fragments into four fragments: a 0.5kg, a 1kg, a 1.5kg and a 2kg object.

What force does each of those fragments have (and thus what acceleration)?

My assumption is that it will get a percentage of the force relative to the percentage of the mass. So the 1kg fragment is 1/5th of the original mass thus it gets 1/5th of the force?

share|improve this question
add comment

1 Answer

up vote 1 down vote accepted

It explodes with a force of 500N.

This sentence is nonsensical. It can explode and release some energy. It can also explode and impart a very high force onto the fragments (which sill be different for each fragment) for a very short time interval.

Once the explosion takes place, the fragments will not accelerate (they may decelerate due to air drag, and of course gravity accelerates them). They only accelerate at the moment of the explosion, and this acceleration is highly dependent on the mechanics of the explosion.

share|improve this answer
    
Okay to rephrase: if the explosion has 500J of energy, what kind of acceleration will each fragment get? –  R Bowen May 17 '13 at 6:10
    
@RBowen: highly dependent on the mechanics of the explosion. We usually assume that the acceleration is near-infinite and occurs only for a very short period of time. (See: en.wikipedia.org/wiki/Impulse_(physics) ) –  Manishearth May 17 '13 at 6:13
    
Well my task is to simulate an explosion, not of any particular type, it just has to be an object that explodes. My only problem was how much acceleration to give each fragment. –  R Bowen May 17 '13 at 6:40
    
@RBowen: It could be anything you want. Remember, the acceleration is only for a very small moment, so what is more important is the final velocities. Make sure you conserve momentum and energy when deciding the velocities. –  Manishearth May 17 '13 at 6:42
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.