Velocity dependent forces problem

  • Thread starter Thread starter retupmoc
  • Start date Start date
  • Tags Tags
    Forces Velocity
AI Thread Summary
To calculate the force exerted when a ball hits a wall at speed V, one can use the change of momentum and the time of contact. The time-averaged force can be determined by dividing the change in momentum by the contact time, as force is defined as the rate of change of momentum (dp/dt). However, in high-speed collisions, the contact time is very brief, leading to a practically infinite force due to the rapid change in momentum. This scenario is often analyzed through the concept of impulse, which is the product of force and time, equating to the change in momentum. Understanding collision theory and impact analysis is crucial for accurately assessing these dynamics.
retupmoc
Messages
47
Reaction score
0
I know of velocity dependent forces and the like but have a problem in grasping a problem I've been thinking over for the past few days although i know the answer is really simple. For exampe when a ball hits a wall at speed V, say how do i work out the force. Is it just by using the change of momentum and time of contact?
 
Physics news on Phys.org
The time-averaged force acting upon the ball can be found in the manner you described.
Notice that this force will be practically infinite, since the contact time is practically zero!

What do you know of collision theory/impact analysis?
 
When collisions happen very quickly we tend to talk of an impulse. Defined as a force multiplied by a time, an impulse is equal to the change of momentum (simply N2 rearranged).

If however you know the change of momentum and the time of contact you can work out the force, as force is dp/dt so just divide the two and you have the force.
 

Thread 'Derivation of Hamilton's Principle: Questions'

I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
View full post »

Similar threads

I The effect of a field on a particle depends on the particle velocity?
Replies
5
Views
1K
B Questions about momentum and force as well as normal force/friction
Replies
35
Views
4K
B The physics of flywheel launchers (like tennis ball shooters)
2
Replies
60
Views
4K
B How to characterize a rubber ball moving horizontally and bouncing off of a vertical wall?
Replies
8
Views
2K
B Terminal Velocity Equation in vertical cylinder with some fluid
Replies
2
Views
1K
B Why is KE not conserved when momentum is?
2
Replies
53
Views
4K
B Understanding Momentum: The Relationship Between Mass, Velocity, and Force
Replies
29
Views
3K
B Newton's 3rd Law interactions with 2nd and 1st Law Partners
Replies
8
Views
2K
I Angular velocity of a rod and what formula to use while solving.
Replies
15
Views
2K
I Work Done/Energy Transferred in One Dimensional Collision
Replies
5
Views
2K

Hot Threads

Recent Insights

Back
Top