Solenoid Practice

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Solenoid worksheet 1. The four diagrams below represent electromagnets connected to the terminals of a battery. In each of the diagrams, indicate the magnetic poles of the electromagnet 2. The magnet in the diagram is constructed from an iron core and a coil of wire connected to a battery. When the switch is turned off, an + electric current circulates through the wire. − Which of the following diagrams correctly shows the magnetic field of this electromagnet? A) C) S N + + − − N S B) D) S N + + − − N S 3. Two of the following diagrams correctly represent the magnetic field created by an electric current flowing through a solenoid. Which two diagrams are they? - + 1. - + 3. I I 2. 4. I I 4. In the solenoid below, which terminal (A or B) of the power supply is positive, and which is negative? 5. An electric current flows through a solenoid. Which diagram correctly illustrates the magnetic field produced by this solenoid? 6. A bar magnet is brought close to a current-bearing electromagnet. Indicate whether there will be attraction or repulsion between the electromagnet and the bar magnet. a) S N b) S N + − − + c) d) S N N S + − − + 7. Which of the following diagrams correctly represents the magnetic lines of force between two solenoids? A B C D 8. On each diagram, draw the magnetic lines of force that are present and indicate the magnetic poles when a current flows through the two solenoids. electron flow electron flow 9. Electric current flows through three solenoids aligned side by side. Solenoid 1 Solenoid 2 Solenoid 3 Determine if there will be attraction or repulsion between the three solenoids. Justify your answer by filling in the information on the solenoids. 10. A compass is placed in a magnetic field. Which of the following diagrams shows the compass needle pointing in the correct direction? A C N S S N D B S N N S 11. Draw the magnetic field lines and put in the current direction for each of the solenoids below. 12. A compass is placed at one end of a solenoid. In which illustration is the compass needle pointing in the right direction? Justify your choice. N S S N S N N S .

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