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So suppose a body of mass 10kg travelling at 5m/s crashes into a wall, the time of deceleration would be very minute, say 0.01 second, then the magnitude of deceleration would be

$$\frac {0-5}{0.01} =\frac {-5}{0.01} = -500m/s^2$$

So the force would be 5000N

Wouldn't such a high force cause a lot of damage? Even a small crash would trigger such high damage? But in reality , I don't think much damage happens..Can you explain why

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    $\begingroup$ Dropping a 10 kg weight on your toes will hurt. May also make dents in floors. $\endgroup$
    – user137289
    Commented Mar 8, 2019 at 10:42
  • $\begingroup$ Really hurt. Don't try that, especially if it's a rock solid, it's a really terrible idea. $\endgroup$
    – TechDroid
    Commented Mar 8, 2019 at 10:54
  • $\begingroup$ What do you consider to be "a lot of damage"? Why do you not think "a lot of damage" should occur? What is a "small crash"? What is the wall made of? What is the body made of? This question is too unclear as it currently is. $\endgroup$
    – BioPhysicist
    Commented Mar 8, 2019 at 12:28

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The damage caused on something involves more than just how much force. 5000 N is some force no doubt, but to most well built brick structures, it's relatively nothing. To picture the damage a force can have on something, you'll have to to also consider the area it's acting over which translates to pressure, defined as: $P=\frac FA$; the greater the pressure, the more damage will be inflicted. That's obviously why hard target projectiles like armor piercing artilleries and 50 call bullet are streamlined for maximum efficiency and tipped acutely for maximum damage.

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  • $\begingroup$ Does the time also play a role in this . I mean like a force 5000N applied for 1 sec vs a force of 5000N applied for 10 sec. Would that play a difference, if so how? $\endgroup$
    – Sarvesh Thiruppathi
    Commented Mar 8, 2019 at 17:43
  • $\begingroup$ Yes it will, but a crash applies all its force almost instantaneous if the wall stops the mass, unless if the 10 kg mass is tearing through the obstruction. In the case of scenario like in the question, it also depends on what sort of wall we're dealing with, if the mass has to tear through the wall over a distance $l$ before being brought to a stop the time of the force exertion through the deceleration tells how much damage inflicted. A more strong and solid wall will experience less damage since it has the strength to take the blow without giving in. $\endgroup$
    – TechDroid
    Commented Mar 8, 2019 at 18:45

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