1. Which of these diagrams shows the magnetic field lines around the north pole of a magnet?
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2. Which one of these could not have a magnetic field around it?
- A). Horseshoe magnet
- B). Electric cable
- C). Copper bar
- D). Compass
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3-7. What are the missing words in this passage?
| In the diagram shown, a wire has a current flowing though it |
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and is placed between two magnets. There is
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between the north and south poles pointing
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This pushes the wire
. If the direction of the current |
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was reversed, the wire would be pushed
. This force |
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is only produced when the direction of the current is
to |
| the direction of the field lines. |
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8. Which one of these appliances does not use the effect described in the last question?
- A). Loudspeaker
- B). Motor
- C). Light bulb
- D). Electric fan
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9. The force on a wire can be made stronger in several ways. Which one of these will not work?
- A). Increase the current
- B). Use stronger magnets
- C). Use a coil with many turns
- D). Make the wires thinner
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10. If you push a metal bar quickly between 2 magnets it produces a voltage in the bar. What is this effect called?
- A). Induction
- B). Reduction
- C). Generation
- D). Production
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11. The diagram shows a coil turning in between two magnets to make a voltage to heat a resistor. What would happen if the coil was rotated faster?
- A). The resistor would stay the same temperature.
- B). The resistor would take more current but stay the same temperature.
- C). The voltage and temperture would increase
- D). The resistor would cool down.
 from www.ncert.nic.in
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12. Which of these methods will not generate a voltage?
- A). Rotate a coil in a magnetic field
- B). Rotate a magnet inside a coil
- C). Move a magnet past a wire
- D). Move a wire past a coil
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13. A.C. generators are found in
- A). C.D. players
- B). Phone chargers
- C). Power stations
- D). Amplifiers
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