# Chapter 29

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question
A circular loop of wire lies flat on a level table top. A bar magnet is held stationary above the circular loop with its north pole point downward. As viewed from above, in what direction does the induced current flow in the loop of wire? a) No current is induced in the loop of wire. b) An induced current flows clockwise in the loop of wire. c) An induced current flows counterclockwise in the loop of wire. d) The direction of the induced current cannot be determined from the given information.
a) No current is induced in the loop of wire.
question
A circular loop of wire lies flat on a level table top in a region where the magnetic field vector points straight upward. The magnetic field suddenly vanishes. As viewed from above, in what direction does the induced current flow in the loop of wire? a) An induced current flows clockwise in the loop of wire. b) No current is induced in the loop of wire. c) An induced current flows counterclockwise in the loop of wire. d) The direction of the induced current cannot be determined from the given information
b) No current is induced in the loop of wire.
question
In the figure, a conducting rod is shown moving in a uniform magnetic field . Which of the following statements are true? Check all that apply. a) An electric field is established in the rod directed from point a to point b. b) The free charges in the rod are acted upon by a magnetic force. c) The magnitude of the potential difference in the rod is proportional to the strength of the magnetic field. d) The magnitude of the potential difference in the rod is inversely proportional to the length L of the rod. e) The magnitude of the potential difference in the rod is proportional to the velocity v of the rod.
a) An electric field is established in the rod directed from point a to point b. b) The free charges in the rod are acted upon by a magnetic force. c) The magnitude of the potential difference in the rod is proportional to the strength of the magnetic field. e) The magnitude of the potential difference in the rod is proportional to the velocity v of the rod.
question
Which of the following statements are true regarding electric generators? Check all that apply. a) An electric generator is used to increase or decrease an alternating current voltage. b) An electric generator converts electrical energy into magnetic energy. c) An electric generator creates a time-dependent induced voltage. d) An electric generator creates a time-independent induced voltage. e) An electric generator converts mechanical energy into electrical energy.
c) An electric generator creates a time-dependent induced voltage. e) An electric generator converts mechanical energy into electrical energy.
question
Which of the following statements are true concerning electromagnetic induction? Check all that apply. a) It is possible to induce a current in a closed loop of wire located in a uniform magnetic field by either increasing or decreasing the area enclosed by the loop. b) It is possible to induce a current in a closed loop of wire without the aid of a power supply or battery. c) It is possible to induce a current in a closed loop of wire remaining at rest and located in a uniform magnetic field. d) It is possible to induce a current in a closed loop of wire by change the orientation of a magnetic field enclosed by the wire. e) It is possible to induce a current in a closed loop of wire by changing the strength of a magnetic field enclosed by the wire.
a) It is possible to induce a current in a closed loop of wire located in a uniform magnetic field by either increasing or decreasing the area enclosed by the loop. b) It is possible to induce a current in a closed loop of wire without the aid of a power supply or battery. d) It is possible to induce a current in a closed loop of wire by change the orientation of a magnetic field enclosed by the wire. e) It is possible to induce a current in a closed loop of wire by changing the strength of a magnetic field enclosed by the wire.
question
In the figure, a conducting rod is shown moving to the right along U-shaped conducting rails. The apparatus is in a uniform magnetic field perpendicular to the plane of the figure. As viewed from above, in what direction does the induced current flow in the U-shaped apparatus? a) An induced current does not flow in the U-shaped apparatus. b) An induced current flows counterclockwise in the U-shaped apparatus. c) The direction of the induced current cannot be determined from the given information. d) An induced current flows clockwise in the U-shaped apparatus.