Ncert- science – class 7- Chapter 10 – Electric Current and Its Effects 1 Welcome to your Ncert- science – class 7- Chapter 10 – Electric Current and Its Effects 1 1. The longer line in the symbol of a cell denotes the negative terminal all of these the direction of current the positive terminal None 2. Electric current is said to be pass through a wire when Only proton pass through it No particle pass through it Both electron and neutron pass through it Only electron passes through it None 3. Electromagnet is used in Dry cell Battery Fuse Electric bell None 4. Electromagnet loses its magnetic property when Current is switched OFF Current is very high Current is switched ON Heat is increased None 5. Which of the following is the best option while considering the safety of household electric appliances ? We should use ISI marked MCBs We should use wire strip as fuses . We should use conductors with high melting point in fuses . We should use non-ISI marked MCBs None 6. The magnetic effect of the current was discovered by _ ? Oersted Ohm Newton Joule None 7. Which of the following is not a component of electric bell? None of the above Ferromagnetic strip Gong Low magnetic field permanent magnet to attract ferromagnetic strip None 8. The strength of the magnetic field due to a solenoid can be increased by by winding solenoid around a plastic rod decreasing the current strength in the solenoid increasing the number of turns in the solenoid all of the above None 9. Which of the following is an advantage of using electrical symbol? All of the above. It makes the representation of electrical component easy. It makes the circuit drawing easier. It helps in solving the circuits. None 10. Electric current is measured by a device 11. Which of the following is an essential element in an electric circuit ? voltmeter switch connecting wires ammeter None 12. A rheostat is used in an electrical circuit to change the potential difference. to change the emf. to change the current through a particular instrument. to change the resistance of the circuit. None 13. Electric current is said to be pass through a wire when No particle pass through it Both electron and neutron pass through it Only proton pass through it Only electron passes through it None 14. A device which prevents or allows the current to flow through it Terminal Switch Conductor Motor None 15. Compact fluorescent lamps (CELs) are considered better than ordinary electric bulbs because ? CFLs reduce wastage Both CFLs reduce wastage and CFLs can be fixed in the ordinary bulb holders . None of these CFLs can be fixed in the ordinary bulb holders . None 16. Filament of electric bulb is made up of Low melting point High melting point High boiling point Low boiling point None 17. Fuse wire is made up of alloys of High melting point Low boiling point High boiling point Low melting point None 18. Electrons are ___________ particles. Negatively charged Positively charged Current Neutral None 19. When an electric current passes through a solenoid, it acts as a/an resistor bar magnet electric bell insulator None 20. Which of the following is a characteristic of a buzzer? It has different mechanism from electric bell. It has higher frequency of collision of gong and hammer None of the above It uses only AC power supply None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
