Relationship between Kinetic Energy and Linear Momentum.

AI Thread Summary
A device can theoretically have kinetic energy without linear momentum if it is in a state of rotation, as rotational motion involves angular momentum rather than linear momentum. The equations for linear momentum (p = mv) and kinetic energy (Ek = ½ mv²) indicate that if mass is moving in a straight line, both quantities are linked. However, if an object is rotating, it can possess kinetic energy due to its motion while having zero linear momentum if its center of mass is stationary. The discussion concludes that it is not possible to create a device with linear momentum but no kinetic energy, as both concepts are inherently connected in linear motion. Thus, the relationship between kinetic energy and linear momentum is crucial in understanding motion dynamics.
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Homework Statement


Q.1 Describe a device which can have Kinetic Energy but no linear momentum.

Q.2 Is it possible to invent a device with linear momentum and no kinetic energy.



Homework Equations


p = mv
Ek = ½ mv²


The Attempt at a Solution


For a "device" to have no linear momentum p = 0, right? But if p = 0 wouldn't Ek just = 0? So would such a "device" be impossible and the answer to Q.2 is no it is not possible.
 
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How about rotation, with angular momentum
 
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