SCIENCE5 3rd PT Review

Which of the following activities can be done using electromagnet?

                                       

• lifting the refrigerator          

• keeping a room well lighted    

• Sweeping the floor 

• Sewing a dress  

What happens when a part of an electromagnet is disconnected?

                                      

• It loses its temporary magnet.     

• The electromagnet becomes a permanent magnet.

• The electricity continues to flow through it.

• There is an increase number of material attracted by the electromagnet.

Electromagnets are made of coils of wire with electricity passing through

                           them. How does an electromagnet work?

                                    

• When an electric current flow through the wire wrapped around an iron core.    

• When an insulated wire is wrapped around an iron rod.

• When no electricity is connected.

• When the wire is wrapped around an iron core.

What should you do if you want to increase the strength of your

      electromagnet?

                                   

• choose a thinner nail

• increase the number of batteries and more coil

• lessen the number of turns of the wire

• use a shorter nail

What would be the effect of adding more coil of wire in an electromagnet

     setup?

• The more coil the lesser magnet  

• The more coil the more battery.

• The more coil the stronger energy of battery.

• The more coil the stronger the electromagnet.

An electric circuit is a path for transmitting electric current.  In which electric circuit will the bulb light?

 

• A

• B

• C & D

• A &B

Last year’s used Christmas light is not functioning because one of the bulbs is busted. Which of the following discusses the disadvantage shown in the used Christmas light?

• In a parallel circuit, the electricity will flow in an alternative way.

• In a parallel circuit, we can use the other bulbs even one is busted.

• In a series circuit, the electricity will not flow to the wires when one of

      the bulb is busted.

• In a series circuit, same electricity will flow in the wires.

You have presented your project about series circuit on class and had a simple demonstration on it. You have removed one bulb and the other bulbs didn’t light. What might be the best explanation to this?  

• Bulbs are busted.

• Energy can’t flow because the line is broken   

• No power supply.

• Switch is broken

An electric circuit is a path for transmitting electric current. What is the effect of changing the number of bulbs in a circuit from 1 bulb to 3 bulb?

• No changes take place.

• The bulbs become brighter.

• The bulbs become dimmer.

• The bulbs stay at the same level of brightness.

An electric circuit is a path for transmitting electric current.

What is the negative effect of adding more batteries in a circuit?

• Adding more batteries makes the light dimmer   

• Adding more batteries makes the wire longer

• Adding more batteries will make the bulb busted

• Adding more batteries will make the bulb light brighter.