A Box of Mass M Is Pressed Against (But Is

question 49

Multiple Choice

A box of mass m is pressed against (but is not attached to) an ideal spring of force constant k and negligible mass,compressing the spring a distance x.After it is released,the box slides up a frictionless incline as shown in the figure and eventually stops.If we repeat this experiment but instead compress the spring a distance of 2x

• A) the box will go up the incline twice as high as before.
• B) just as it moves free of the spring, the box will be traveling twice as fast as before.
• C) just as it moves free of the spring, the box will be traveling four times as fast as before.
• D) just as it moves free of the spring, the box will have twice as much kinetic energy as before.
• E) just before it is released, the box has twice as much elastic potential energy as before.

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Definitions:

REM Behavior Disorder

A rare disorder in which the mechanism that blocks the movement of the voluntary muscles fails, allowing the person to thrash around and even get up and act out nightmares.

EEG Record

A graphical record of electrical activity in the brain, measured by electrodes placed on the scalp, used in diagnosing neurological conditions and in neuroscience research.

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