Page 135 - Science Class 07

5. In which of the following devices electromagnet is used?
(a) Generator (b) Motor

(c) Loudspeaker (d) All of these
B. Fill in the blanks.
1. Current electricity exits when electricity flows by means of wires in the form of
______________ .
2. There are two types of electric circuit namely ______________________ circuit and
______________ circuit.
3. ______________ is used to connect devices with the help of conductors.

4. When the electric current passes through a conductor, it loses a part of whole
______________.
5. Fuse are generally rated according to the amount of __________________ supplied
through the circuit.
C. Name these devices and their func ons.

1. ______________ 2. ______________ 3. ______________ 4. ______________

D. Very short answer ques ons.
1. What is current electricity?

2. What is electric circuit?
3. What is galvanometer?
4. What do you mean by short circuit?
5. Name any five devices or equipments in which electromagnets are used.

E. Short answer ques ons.
1. What do you mean by poten al difference?
2. Differen ate between open and closed circuit.
3. Describe hea ng effects of electric current.

4. Why do we use an electric fuse and how does it work?
5. Write magne c effects of electric current.
6. Write important uses of electromagnets.

7. How electromagnet is made?
8. Write the construc ons and working of electric bell.
F. Long answer ques ons.
1. What is electricity?

Science-7 135