Science CLASS VII

ELECTRIC CURRENT AND ITS EFFECTS

Q1.Fill in the blanks :

1. A combination of two or more cells is called a _____________ .

2. The working of a an electric bulb, electric iron and the fuse is based on the __________________ effect of current.

3. The filament of an electric bulb is made up of ____________ 

4. Instead of electric bulbs, it is advisable to use __________________ , in order to reduce wastage.

5. __________ is a safety device which prevents fires and damage to electrical Appliances.

6. A current carrying coil wrapped around a piece of iron is called an __________.

7. Electric fuse has ________ melting point.

8. _________________ and _____________ are devices which have electromagnets in them.

9. Amount of heat produced in a wire depends on the length,materal and _________ of the wire.

10. In a fan energy gets converted into ___________ energy

11.Two devices where heating effect of electric current is used are ___________ and _____________

12.Heating effect is more in  long wire and ______________ in a short wire. wire .

13. When a magnetic compass is brought near a circuit carrying current it shows ________________

14.___________ is a device which is wound around  a hollow metallic core and used as an elecromagnet.

15. Draw diagram of a closed electric circuit using symbols which consists of

-two cells (battery),-a switch,-bulb and wire.Also show the direction of electric current

What will happen if we bring a magnetic compass near it.

 Answers-Battery ,heating effect ,tungsten, CFL,  fuse ,electromagnet, low, electric bell and loud speakers ,thickness, mechanical, electric toaster and electric iron, less, deflection, solenoid

mechanical, electric toaster and electric iron, less, deflection,solenoid