A calculus book weighing 20 N rests on the floor of a classroom. The reaction to the force of the floor on the book is a force of
A. 9.8 m/s2 exerted by the Earth on the book.
B. 2.04 kg exerted by the floor on the book.
C. 20 N exerted by the book on the Earth.
D. 0 N.
E. 20 N exerted by the book on the floor.
Answer: C
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A note is being played on a string on a guitar. The string is then pushed to the side while still in contact with the same fret. What happens to the frequency of the note then played compared to the original note?
a. It is the same note since the same fret is being used. b. It is at higher frequency than the original note. c. It is at lower frequency than the original note. d. It can be either higher of lower frequency depending on whether the original note was above or below middle C.
A loop of wire is oriented in the magnetic field as shown (the plane of the loop is perpendicular to the direction of the magnetic field and the magnetic field strength increases with height). Which of the following is true? 
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Identical 4.0-?C charges are placed on the y axis at y = ±4.0 m. Point A is on the x axis at x = +3.0 m. Determine the electric potential of point A (relative to zero at the origin)
a. ?4.5 kV b. ?2.7 kV c. ?1.8 kV d. ?3.6 kV e. ?14 kV
A 0.17-kg baseball is thrown with a speed of 38 m/s and it is hit straight back toward the pitcher with a speed of 62 m/s. What is the magnitude of the impulse exerted upon the ball by the bat?
What will be an ideal response?