A Star Is Moving Towards the Earth with a Speed

question 50

Multiple Choice

A star is moving towards the earth with a speed at 90% the speed of light.It emits light,which moves away from the star at the speed of light.Relative to us on earth,what is the speed of the light moving toward us from the star?

• A) 0.90c
• B) c
• C) 1.1c
• D) 1.20c
• E) 1.9c

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Definitions:

Mean

The average of a set of numerical values, calculated by adding all the figures together and then dividing by the number of values.

Population Standard Deviation

Square root of the population variance that represents the average deviation of a score from the population mean.

Confidence Interval

Re-formulated: An estimate expressing the degree of uncertainty or certainty in a sampling method.

Mean

The average of a set of numbers, calculated by dividing the sum of these numbers by the count of numbers.