Safer Collision: Front-end Damage vs. No Damage - Impulse-Momentum Theorem

  • Thread starter Thread starter pebbles
  • Start date Start date
AI Thread Summary
A collision where the front end of a car is crumpled is considered safer than one with no damage, according to the Impulse-Momentum Theorem. This theorem indicates that a force applied over time reduces the impact force, thereby decreasing potential damage. In the first scenario, the energy is absorbed by the crumpled front end, which mitigates the force experienced by the occupants. Conversely, in a no-damage scenario, the cars bouncing off each other may result in a more abrupt change in momentum. Overall, the discussion emphasizes that energy absorption through deformation is crucial for safety in collisions.
pebbles
Messages
95
Reaction score
0
[SOLVED] What would you say...

Which is safer, a collision in which the front end of a car is completely crumpled, or a collision in which no damage is done to the car, but the two cars bounce backwards off one another. Use the Impulse-Momentum Theorem.

Hm. Well, the Impulse-Momentum Thm. says that a faorce exerted over some time, impulse, causes a change in momentum. So, by increasing the time over which a force must act to stop motion, the force can be reduced and the potential damage reduced. So, the scenario that is safer...logically I'm thinking the second scenario, but I'm not really thinking as a physicist. I'm just thinking that if there's no damage, it has to be safer.
 
Physics news on Phys.org
Would you rather be riding in a car with a spring supported bumper, or one with a rigid 'no - give' bumper? Or if you jump from a building, is it better to land with legs stiff and erect, or bend your knees as you hit the ground?
 
pebbles said:
Which is safer, a collision in which the front end of a car is completely crumpled, or a collision in which no damage is done to the car, but the two cars bounce backwards off one another. Use the Impulse-Momentum Theorem.

Use the Impulse-Momentum Theorem

Think on this line: In which case change in momentum is more? Then, assuming time of impact to be same, you can calculate in which case impulse is more.
 
now that you put it that way, it seems to make more sense. so, the first scenario would be safer because the energy is absorbed by the front end of the car...
 
pebbles said:
now that you put it that way, it seems to make more sense. so, the first scenario would be safer because the energy is absorbed by the front end of the car...

It's why those barrels at the entry to a highway exit ramp are filled with sand (to go 'splash' on the occasion someone's car rams them), rather than a nice big synthetic rubber bumper...
 
ok. thanks everyone. it makes sense now.
i greatly appreciate it!
:]
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »

Similar threads

Work done during a collision -- Change in Kinetic Energy & change in Momentum
Replies
1
Views
2K
How does changing the duration of a collision affect impulse
Replies
1
Views
2K
How Does Impulse Relate to Momentum Change in Physics Problems?
Replies
7
Views
2K
Momentum and impulse of a football
Replies
2
Views
2K
Elastic collision of particle and rotating disc
Replies
7
Views
2K
Horizontal impulse on a ball at rest on a plane (with friction)
Replies
14
Views
3K
Collision Experiment: Momentum, Impulse and Conclusions
Replies
16
Views
2K
Impulse exerted on car during collision
Replies
4
Views
2K
Comparing Impulses in Unequal Mass Collisions
Replies
1
Views
2K
Momentum: why don't the two carts become one?
Replies
32
Views
1K

Hot Threads

Recent Insights

Back
Top