This quiz works best with JavaScript enabled. Home > Class 7 > Class 7 Science Chapter 10 Electric Current And Its Effects – Quiz 29 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 29 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. If the battery produced 12.6 V and what would be the current flow be for a 6 $\Omega$ resistor A) 2.1 A. B) 2.4 A. C) 1.71 A. D) 15 A. Show Answer Correct Answer: A) 2.1 A. 2. Filament of a bulb is made up of ..... because it offers very high resistance. A) Copper. B) Silver. C) Iron. D) Tungsten. Show Answer Correct Answer: D) Tungsten. 3. A fuse is used to save energy in electrical circuits. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 4. In dry cell it acts as positive terminal A) Zinc case. B) Carbon rod. C) Both. D) None of the above. Show Answer Correct Answer: B) Carbon rod. 5. Which of the following is NOT a chemical reaction caused by electric current passing through liquids A) The colour of the electrolyte changes. B) Metal coating can be formed on the electrodes. C) Bubbles can form near the electrodes. D) Different smells can be released. Show Answer Correct Answer: D) Different smells can be released. 6. The magnetic effect of electric current was discovered by- A) Maxwell. B) Darwin. C) Oasted. D) Newton. Show Answer Correct Answer: C) Oasted. 7. Electromagnets are ..... A) Permanent magnets. B) Temporary magnets. C) Natural magnets. D) None. Show Answer Correct Answer: B) Temporary magnets. 8. The device used to detect the direction of a current-carrying conductor in a magnetic field is called: A) Ammeter. B) Voltmeter. C) Galvanometer. D) Rheostat. Show Answer Correct Answer: C) Galvanometer. 9. Name of the scientist who discovered magnetic effect of electricity A) Thomas Edison. B) Hans Christian Oersted. C) Alexander G Bell. D) None of these. Show Answer Correct Answer: B) Hans Christian Oersted. 10. Substances through which electric charges cannot move freely- A) Insulators. B) Conductors. C) Wood. D) Plastic. Show Answer Correct Answer: A) Insulators. 11. Which one cools down slower? A) Water. B) Air. C) Land. D) None of the above. Show Answer Correct Answer: A) Water. 12. To change the direction of current in the armature, following device is used: A) Pole pieces. B) Carbon brushes. C) Battery. D) Split ring or commutator. Show Answer Correct Answer: D) Split ring or commutator. 13. The Earth's greatest source of energy comes from the ..... A) Precipitation. B) Rotation of its axis. C) Sun. D) Oceans currents. Show Answer Correct Answer: C) Sun. 14. You open a switch to stop the flow of electricity.True or false A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 15. Which of the following cannot be an example for the use of electromagnets A) Electric Bell. B) Passionate. C) Oven. D) Phone. Show Answer Correct Answer: C) Oven. 16. During electrolysis of water, A) Hydrogen gas is produced. B) Oxygen gas is produced. C) Water is produced. D) Both (a) and (b). Show Answer Correct Answer: D) Both (a) and (b). 17. Do electric currents move slow or fast? A) Slow. B) Fast. C) All the above. D) None of the above. Show Answer Correct Answer: A) Slow. 18. When acidified water is electrolysed using carbon electrodes. What is produced at (+) and (-) electrodes. A) (+)-Oxygen; (-)-Hydrogen. B) (+)-Oxygen; (-)-Carbon. C) (+)-Hydrogen (-)-Oxygen. D) None of the above. Show Answer Correct Answer: A) (+)-Oxygen; (-)-Hydrogen. 19. Atoms contain ..... types of subatomic particles. A) 1. B) 2. C) 3. D) 4. Show Answer Correct Answer: C) 3. 20. Which one is the polluting waste generated by electroplating factories? A) Used up electrodes. B) Electrolytes. C) Corroded Metals. D) None of the above. Show Answer Correct Answer: B) Electrolytes. 21. How does corrosion occur in metals? A) Corrosion occurs in metals when they react with substances in the environment, such as oxygen and water. B) Corrosion is caused by metals being exposed to strong magnetic fields. C) Corrosion happens in metals when they are stored in a vacuum. D) Corrosion occurs in metals due to excessive heat exposure. Show Answer Correct Answer: A) Corrosion occurs in metals when they react with substances in the environment, such as oxygen and water. 22. What unit is used to measure current? A) Ohms. B) Omega. C) Volts. D) Amps. Show Answer Correct Answer: D) Amps. 23. Electric potential is measured in ..... A) Volts. B) Amps. C) Friciton. D) None of the above. Show Answer Correct Answer: A) Volts. 24. Generators are devices that convert ..... energy into ..... energy. A) Chemical; mechanical. B) Mechanical; electrical. C) Electrical; mechanical. D) Potential; kinetic. Show Answer Correct Answer: B) Mechanical; electrical. 25. One of the following is not used for electroplating metal articles. the one is- A) Nickel. B) Chromium. C) Sodium. D) Silver. Show Answer Correct Answer: C) Sodium. ← PreviousNext →Related QuizzesClass 7 Science Chapter 10 Electric Current And Its Effects Quiz 1Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 2Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 3Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 4Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 5Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 6Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 7Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 8Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 9Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books