Ncert- science – class 7- Chapter 10 – Electric Current and Its Effects 2 Welcome to your Ncert- science – class 7- Chapter 10 – Electric Current and Its Effects 2 1. What must happen for an electromagnet to have a magnetic field? It must be lined up with earth's magnetic field It must be connected to an electrical source. It must be touching another magnet. It must be heated. None 2. When electric current passes through the filaments of a bulb, it starts emitting light due to: Magnetic effect of electric current Heating effect of electric current Lighting effect of electric current Chemical effect of electric current None 3. Which pair is not correct for the instruments used in the laboratory and their uses from the following? Ammeter - To measure the electric current Galvanometer - To detect the presence of current Resistor - To supply the electric energy to circuit Voltmeter - To measure the electric potential differene None 4. An electric bell works on the .......... effect of a current and uses an .......... Heating, Permanent magnet Heating, Electromagnet Magnetic, Permanent magnet Magnetic, Electromagnet None 5. A fuse is used in an electrical appliance : To change the current rating of the applicance To earth the appliance To protect the appliance and its cable To change the efficiency of the applicance None 6. Which one of the following heater element is used in electric press Copper wire Iron wire Lead wire Nichrome wire None 7. Electromagnets are made up of: copper aluminum steel Soft iron None 8. The components required to make a simple series circuit to light a bulb are Both Cell, switch and Bulb, wires Cell and switch Bulb and wires Wires and cell None 9. The essential requirements for a good heating element are _________________. Low resistivity and low melting point High resistivity and low melting point High resistivity and high melting point Low resistivity and high melting point None 10. When the switch of an electric bell is on then electric current in it : Flows in beginning and then stops forever Flows and stops in succession Flows continuously First flows in one direction and after sometime in other direction None 11. What happens to a circuit when the switch is off? The circuit is complete There is a gap in the circuit Electricity flows continuously Electricity flows discontinuously 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.
