Formula involving the change in a kinetic energy

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Homework Help Overview

The discussion revolves around a problem involving the change in kinetic energy of a box subjected to a force. The scenario includes a 120 N force applied at an angle to a 4 kg box moving a horizontal distance of 8 meters.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the relationship between work done and change in kinetic energy, with suggestions to calculate vector components of the applied force and consider initial conditions such as initial velocity.

Discussion Status

Some participants have offered guidance on breaking down the force into components and relating work done to energy changes. Multiple interpretations of the problem are being explored, particularly regarding the role of potential energy and initial conditions.

Contextual Notes

Assumptions about initial velocity and the presence of gravitational potential energy are under discussion, with varying interpretations of how these factors influence the overall energy calculations.

electrical_ck
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I'm looking for a formula involving the change in a kinetic energy, I have a 120 N force applied at an angle of 30 degrees above the horizontal to a 4kg box. The box moves a horizontal distance of 8 meters. The change in the kinetic energy of the box is:

Just looking for a formula to figure this one out
 
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The work done by the force on the box=Change in kinetic energy of the box.
 
Hi,...What equations do you have for work? Calculate the vector components of the 120N force. This will simplify the problem for you.
 

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If you assume the initial velocity is 0, you know that the final energy of the box is E = K + V, K being the kinetic energy and V being the potential. If gravity is involved, your potential V is mgh. If not, it's 0. You also know that your total energy, or the work done to the box, is equal to F \cdot d\overrightarrow x. Break down the force into its components to determine the work done.
 
Last edited:

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