A 10-kg block is pushed across a horizontal surface with a horizontal force of 30 N against a friction force of 10 N. The acceleration of the block is
A) 1 m/s2.
B) 2 m/s2.
C) 5 m/s2.
D) 10 m/s2.
E) none of the above
Question 2
You give your physics book a quick push so that it slides along a table top. It soon slides to a stop. How would Aristotle and Galileo interpret this?
A) They agree that physics books can make you crazy and it's best not to think about them.
B) Both of them say that this is just the natural motion of the book.
C) Both of them say the force of friction slows it to a stop.
D) Aristotle says this is just the natural motion of the book, but Galileo says the force of friction slows it to a stop.
E) Aristotle says the force of friction slows it to a stop, but Galileo says this is just the natural motion of the book.
The Sun's Surface
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finding the resultant force
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