A Block, Moving on a Frictionless Horizontal Surface on Earth

question 28

Multiple Choice

A block, moving on a frictionless horizontal surface on Earth, requires a force if it is to be stopped. Now suppose that the same block, moving with the same speed on a frictionless horizontal surface on the Moon, where gravity is less, is to be stopped in the same time. We can say that, compared to the Earth,

• A) less force is required to stop the block on the Moon.
• B) the force required would be the same.
• C) greater force is required to stop the block on the Moon.
• D) the block could not be stopped.

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Definitions:

Radical Activists

Individuals or groups who take extreme actions to effect change in pursuit of their political, social, or environmental goals.

Laboratory Experiments

Research methods that involve the manipulation of one or more variables in a controlled environment to observe the effects on behavior.

Confounding Variables

These are variables that the researcher failed to control, or eliminate, damaging the internal validity of an experiment by providing a possible alternative explanation for outcomes.

External Validity

How broadly the outcomes of a research project can be extended to different contexts and populations.