The Sum of the Kinetic and Potential Energies of a System

question 52

Multiple Choice

The sum of the kinetic and potential energies of a system of objects is conserved:

• A)only when no external force acts on the objects
• B)only when the objects move along closed paths
• C)only when the work done by the resultant external force is zero
• D)always
• E)none of the above

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Definitions:

Random Sample

A selection process where each member of a population has an equal chance of being included in the sample, minimizing bias.

Population

In statistics and demography, a comprehensive group of individuals or items that share one or more characteristics from which data can be gathered and analyzed.

Double-blind Study

A study design in which neither the participants nor the researchers know which participants belong to the control group and which belong to the experimental group until the conclusion of the research.

Experimental Drug

A pharmaceutical compound that is in the process of being tested for effectiveness and safety in treating a particular disease or condition but has not yet received governmental approval for general use.