force necessary to lift vertically a mass knowing the altitude at a given moment.

[shinobi9]

Good morning.
I need an answer to this question: Imagine having a mass, therefore, a material point of 50 kg and wanting to raise it vertically by means of an "impulsive" force. . having as objective that in a certain deltat must be climbed to a certain quota.. How would you proceed? I tried to write to me the equation of newton that is trivial the point is that according to me you get to a differential equation with forceful f(t) modelable analytically with step..so to solve also numerically by software like simulink..How would you do alternatively? Among other things the mass at the maximum point the dynamic changes and becomes trivially subject only to weight...I do not ask for practical usefulness but it is something that came to mind.

 

[cacciatorino]

Good morning.
I need an answer to this question: Imagine having a mass, therefore, a material point of 50 kg and wanting to raise it vertically by means of an "impulsive" force. . having as objective that in a certain deltat must be climbed to a certain quota.. How would you proceed? I tried to write to me the equation of newton that is trivial the point is that according to me you get to a differential equation with forceful f(t) modelable analytically with step..so to solve also numerically by software like simulink..How would you do alternatively? Among other things the mass at the maximum point the dynamic changes and becomes trivially subject only to weight...I do not ask for practical usefulness but it is something that came to mind.

You must define the duration of your impulse t, otherwise the contribution of inertial resistance is not quantifiable.

 

[shinobi9]

Okay, but as a method of calculation? should you set the equation of newton and solve in a numerical way the differential equation resulting from it?

 

[cacciatorino]

Okay, but as a method of calculation? should you set the equation of newton and solve in a numerical way the differential equation resulting from it?

Excuse ignorance, what do you mean as a newton equation? you must define a motion law with acceleration, drawn at constant speed (possibly not present) and deceleration until the point of arrival. under these assumptions you find the acceleration and consequently the inertia force to be added to the weight force.

 

[ragnol]

I press that I am ignorant as a goat, and I do not say it for false modesty but because unfortunately it is so, but the son (adult) of my owner asked me if I checked the fixing to the foot of a crane that we have in company, from the night of the times, as it changed the organ of raising that flows on the horizontal profile and wanted to know if the structure can carry the "3000 kg" that are indicated on the new argano.
to nothing it has served to try to make him understand why I needed to know, besides the maximum shooting of the Argan, also the maximum vertical acceleration that the Argan could exercise on the limit load itself. ..according to him if the armor raises 3000kg that is the value I had to use, point!
if you feel that my speech exposes the thread, delete as well

 

[cacciatorino]

I press that I am ignorant as a goat, and I do not say it for false modesty but because unfortunately it is so, but the son (adult) of my owner asked me if I checked the fixing to the foot of a crane that we have in company, from the night of the times, as it changed the organ of raising that flows on the horizontal profile and wanted to know if the structure can carry the "3000 kg" that are indicated on the new argano.
to nothing it has served to try to make him understand why I needed to know, besides the maximum shooting of the Argan, also the maximum vertical acceleration that the Argan could exercise on the limit load itself. ..according to him if the armor raises 3000kg that is the value I had to use, point!
if you feel that my speech exposes the thread, delete as well

In theory he's right: if the armor pulls 3,000 pounds in there, there's already the contribution of inertia and weight. If you have a strong acceleration you will decrease the load lifted because the sum of the two contributions must always make 3000 that is the maximum that can give you the winch

experience, except for extreme dynamics, in cases of lifting the contribution of inertia is minimal compared to that of weight.

 

[shinobi9]

I understood what you mean. I thought I could solve it by applying the law of newton in the sense that I banally have \[ mx''(t)=F(t)-mg \] that I go to integrate numerically giving to the f(t) its trend.però with an impulsive f(t) precisely because it acts in the initial instant.

However to answer the other question I would say that it depends if here 3000 kg already take into account the inertia force as well as the weight...

 

[ragnol]

In theory he's right: if the armor pulls 3,000 pounds in there, there's already the contribution of inertia and weight. If you have a strong acceleration you will decrease the load lifted because the sum of the two contributions must always make 3000 that is the maximum that can give you the winch

experience, except for extreme dynamics, in cases of lifting the contribution of inertia is minimal compared to that of weight.

In the strict sense I wanted to highlight how in the "praticone" environment often we do not consider acceleration (or better, the force that comes) in the evaluations. . .
I agree that the acceleration of the load during lifting is usually modest.. .