# Linear/angular Momentum / tripping / conservation

## Homework Statement

An rectangular object(mass m) sliding on a horizontal plane (surface is frictionless), with a speed V, object height H.
then hits a rectangular obstacle with height h. V is large enough to cause tripping

## Homework Equations

what is the relation between linear momentum / angular momentum / conservation of momentum

## The Attempt at a Solution

is this what's happening; the object has a momentum of P=mV.
then an impulse I=t*F is applied to the object by the obstacle.
This impulse reduces the linear momentum to P'=m*V-F*x
---This m*V-Fx gives the angular momentum(with respect to the point of contact) causing the rotation?---

I am not sure if my thinking is correct, especially my last statement.

An alternative is; taking initial mV as an angular momentum with changing radius wrt the contact point??? ie not mentioning linear momentum at all?

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haruspex
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is this what's happening; the object has a momentum of P=mV.
then an impulse I=t*F is applied to the object by the obstacle.
It won't be useful to introduce F or t. Just leave it as I.
This impulse reduces the linear momentum to P'=m*V-F*x
x?
---This m*V-Fx gives the angular momentum(with respect to the point of contact) causing the rotation?---
I provides the angular momentum.
To solve the problem, you need to use a fact concerning subsequent motion of the block.. like, some point that is stationary immediately after impact.

It won't be useful to introduce F or t. Just leave it as I.

x?

I provides the angular momentum.
To solve the problem, you need to use a fact concerning subsequent motion of the block.. like, some point that is stationary immediately after impact.
Thanks a lot haruspex.

x was wrong, well spotted. It should be 't'.

what I am trying to do is derive a formula to show the affect of speed on the tripping.

Assuming the object is a car and the obstacle is a concrete block; I would like to find out what's the speed above which the car will trip. So the top of concrete can be the reference point.

I know the mass, I know the object height and center of gravity and obstacle height. I am still struggling to figure out writing the equation. Not sure if I need to use momentum equations or energy equations.

haruspex
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