ACTIVITY 3: THE CHOICE IS YOURS!
Directions: Read each item carefully. Choose the letter of the best answer.
____1. What is the advantage of an electromagnet compared to a permanent magnet?
A. Electromagnet is lighter.
B. Electromagnet can be turned on and off.
C. Permanent magnet cannot be used to pick up metals.
D. Electromagnet can be used for attracting more metals.
____2. What are the factors that affect the strength of an electromagnet?
A. Battery, magnet, and core
B. Dry cells, nail, and magnet
C. Number of coil, number of magnets, and wire
D. Number of coils/wire, number of batteries/dry cells, and properties of the core
____3. What could make an electromagnet stronger?
A. Use a weaker battery.
B. Reverse the poles of the magnet.
C. Remove all the coils and the nail.
D. Add more coils of wire to the nail.
____4. Complete this sentence:
"In order to form an electromagnet, a/an _______ current should flow through a coil of
______ covered around a/an ______ core. "
A. Electric, wire, iron C. Iron, electric, wire
B. Iron, wire, electric D. Wire, iron electric
_____5. You conducted an experiment using a very strong electromagnet. How can
you make it weaker?
A. Add more loops. C. Add more batteries.
B. Use a thicker wire. D. Wrap the wire loosely.
(LAS)-Science week 6 QR-3