A Relatively Fast Star Escapes an Open Cluster

question 237

Multiple Choice

A relatively fast star escapes an open cluster. What does this do to the stability of the remaining cluster?

• A) The remaining cluster becomes MORE stable because only the slower stars are left.
• B) The gravitational attraction of the escaping star tends to pull other stars after it, thus leading to the dissipation of the entire cluster.
• C) The remaining cluster becomes LESS stable because the mass and thus the escape speed are reduced.
• D) Because of the conservation of momentum, a second star must be expelled from the cluster in the opposite direction. The remaining cluster is then as stable as it was originally.

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Definitions:

Systematic Variance

The portion of variation in an outcome that can be consistently explained by variables or factors in a study.

Error Variance

The variability in a set of data that cannot be attributed to the factors being studied, often resulting from measurement errors or other inconsistencies.

Dependent Sample Designs

Research designs involving comparisons of measurements from the same group of subjects under different conditions or at different times.

Extraneous Variables

Factors in a study that could undermine the internal validity by influencing the dependent variable in a way not intended by the research.