A cliff diver' in Mexico dives off a high cliff and falls for 2.3 seconds before hitting the water. (a) How fast is the diver going at impact? (b) How far below the cliff is the diver at this point?
[Ques. 2] What is an electromagnet?
a. All magnets are electromagnets.
b. An unscientific term based on confusing electricity with magnetism.
c. An electrical coil wrapped around an iron core.
d. Another name for a magnetic pole.
e. A device that attracts electrons.
[Ques. 3] A race car goes around a curve at 50 m/s. The radius of the curve is 400 m. What is the car's acceleration?
[Ques. 4] Which of the following statements is currently believed to be true?
a. Electricity is caused by magnetic current loops at the atomic level.
b. Magnetism is caused by electric current loops at the atomic level.
c. All electric fields are produced by moving magnetic poles.
d. Stationary electric charges produce magnetic fields.
e. Steady magnetic fields create electric fields.
[Ques. 5] The acceleration of a ball as it rolls down a ramp is 3 m/s2 . It starts from rest. (a) What is the ball's speed after 4 seconds? (b) How far does the ball travel during the 4 seconds?
[Ques. 6] How would a compass needle align itself in the magnetic field shown in this figure?
a. It would align itself along the magnetic field lines circling the wire, with the north pole of the compass pointing clockwise.
b. It would align itself along the magnetic field lines circling the wire, with the north pole of the compass pointing counterclockwise.
c. The compass needle aligns perpendicular to the magnetic field with its north pole pointing directly at the wire.
d. The compass needle aligns perpendicular to the magnetic field with its north pole pointing directly away from the wire.
e. The direction the compass tends to point is up out of the page, but it cannot rotate that way, and it therefore does not respond to the magnetic field.
[Ques. 7] During takeoff a jet aircraft goes from 0 m/s to 60 m/s in 5 seconds. (a) What is the jet's acceleration? (b) What is the jet's speed after 22 seconds?
[Ques. 8] A compass needle is a magnet with a north and south pole. If a tiny compass were placed in the magnetic field shown in the figure, how would the compass needle aligned in the magnetic field?
a. The needle would line up with a magnetic field line with the compass needle pointing in the same direction as the arrows in the diagram.
b. The needle would line up with a magnetic field line with the compass needle pointing in the opposite direction to the arrows in the diagram.
c. The compass needle always aligns perpendicular to the magnetic field lines.
d. The north pole of the compass will point directly at the north pole of the magnet, regardless of the field lines.
e. The north pole of the compass will point directly away from the north pole of the magnet, regardless of the field lines.
[Ques. 9] A runner in a race takes 2.7 seconds to go from the 40 meter mark to the 70 meter mark. (a) What is the runner's speed? (b) How far would the runner go in 8 seconds if this speed is maintained? (c) How long did it take the runner to cover the first 40 m (assuming the same speed was maintained)?
[Ques. 10] Which is a key difference between electric charges and magnetic poles?
a. Electric charges can be separated while magnetic poles always occur together as opposite poles of equal strength.
b. Magnetic monopoles exist but isolated electric charges are never found.
c. Like electric charges repel but like magnetic poles attract.
d. An electrically charged rod attracts an electrically neutral object but a magnet does not attract and unmagnetized chunk of iron.
e. In electricity, unlike charges repel, but in magnetism, unlike poles attract.
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