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True or false: There is only one possible choice of system which could be correct when doing problems using work and energy.

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Answer:

the relationship is scalar, it is independent of the specific reference system

The statement is false

Step-by-step explanation:

When the concepts of work and energy are being used, a reference system must be defined to perform the calculations,

in the case of work it is defined by the relation

W = F. d

where the point represents the scalar product, therefore the work is a scalar magnitude, it has only modulus for which any reference system is selected since the result is independent of the direction of the force, only the projection of the force depends in the given direction.

For the part of the energy it therefore has two main forms, kinetic energy and potential energy.

For kinetic energy the expression is

K = ½ m v²

therefore, the energizes only depends on the speed module and any reference system, since it will be selected

for gravitational and elastic power energy. It does not depend on the specific value at the point but on the difference with respect to an arbitrarily defined zero, therefore, as the difference is constant, it is independent of the reference system used.

In conclusion, since the relationship is scalar, it is independent of the specific reference system, so we can select several reference systems

User JPGConnolly
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