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QuizMultiple Choice

Universal Law of Gravitation — Unit test

Question 3 • Crowley Credit Recovery Physics A

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. The astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. She has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. Simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. The button is located a short distance behind and below the astronaut’s hands.

Answer
A
The astronaut should toss the penny straight up as it will appear to fall in an arc because objects in an accelerating frame of reference behave in the same way as they would in a gravity field.
B
The astronaut should just let the penny go, as the control panel will accelerate upward and curve toward the astronaut because there is no gravity field.
C
The astronaut should toss the penny horizontally straight behind her as it will appear to fall in an arc because objects in an accelerating frame of reference behave in the same way as they would in a gravity field.
D
The astronaut should toss the penny in a straight line toward the button because the penny will follow a straight line in space rather than appear to move in an arc as it would in a gravity field.

Explanation

The spacecraft accelerates toward the ceiling, so in the astronaut’s frame the penny appears to fall in the opposite direction, toward the floor. Tossing it straight behind gives it motion toward the button, while its apparent downward motion makes its path curve toward the button below her hands. The correct choice is to toss the penny horizontally straight behind her.

AI-written and checked against the verified answer.

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