Work energy method and impulse momentum method

[chandran]

we have two concepts

1)if force is applied for a distance x(i.e work) it increases the kinetic energy of a mass

2)if force is applied for a time t(i.e impulse) it increases the momentum of the mass

why there are two concepts. Are the above two same?

 

[russ_watters]

Neither of those things you just said are correct. Work and kinetic energy are not the same thing and impulse and momentum are not the same thing either.

 

[charng]

The work-energy method and impulse-momentum method are two different concepts that are used to analyze the motion of objects. While they both involve the application of a force to an object, they focus on different aspects of the motion.

The work-energy method is based on the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred from one form to another. When a force is applied to an object and causes it to move a distance x, work is done on the object and its kinetic energy increases. This method is useful for analyzing the motion of objects in terms of their energy, such as calculating the work done by a force or the change in kinetic energy of an object.

On the other hand, the impulse-momentum method is based on the principle of conservation of momentum, which states that the total momentum of a system remains constant unless acted upon by an external force. When a force is applied to an object for a period of time t, it causes a change in the object's momentum. This method is useful for analyzing collisions and other interactions between objects, as it allows us to calculate the change in momentum and therefore the resulting motion of the objects.

Although both methods involve the application of a force and result in a change in an object's motion, they are not the same. The work-energy method focuses on the energy aspect of motion, while the impulse-momentum method focuses on the momentum aspect. This is why there are two concepts – they each offer a different perspective and can be applied in different situations. Both methods are important tools in the study of motion and are used to analyze different aspects of an object's behavior.