Dear all,
This post is created specifically for you to post any query you have while doing your revision.
DO NOT post your problem in CBox as I might not be able able to track all questions asked by you. From Tuesday till Friday, I will only be able to check this blog at night as the PSLE Marking Exercise will only end in the late evening. So, I might not be able to answer your query immediately.
If any of you are able to help to clarify doubts that your friends are facing, feel free to do so. However, I will also check to ensure the problems have been correctly answered by your peers.
Teacher,
ReplyDeleteI have a question on science on magnet. John placed a freely suspended magnet mext to a coil of wire and it moved away. Why? Is it because wire is made of a material which is of good conductor of heat and the magnet repel when it placed next to it as only magnet attracts and repel. Magnetic object can only attracts but not repel?
Sorry, i mean wire is made of a material which is of good conductor of electricity not heat.
ReplyDeleteThe coil of wire can be a magnet itself. It does not have to be a good conductor of electricity in order to a be able to repel or attract a magnet.
ReplyDeleteAdam, to clarify what i had typed earlier.
ReplyDeleteA magnet will only repel another metal which is a magnet, not any magnetic material.
The magnet will not repel the coil of wire, it will only attract unless there is a magnet inside the coil of wire.
oh i understand now. Another question teacher. WHen a metal ball. placed into a pail filled with water, some water spilled out. When the same metal ball is placed into a pail filled with sand, the sand did not spill. Is it because the water spill because metal ball has mass and takes up space? The sand did not overflow because it has air spaces in between them?
ReplyDeleteAdam,
ReplyDeleteFirst you need to ensure that you are using the same container for both the sand and water. Both need to have sand or water filled to its brim.
For the water, yes, water will spill from the beaker almost immediately the moment you placed the ball in.
For the case putting it in sand, the ball might not sink to the bottom of the container and that is the likely reason why the sand did not spill out. However, if you try pushing the ball till it is at the bottom of the beaker, some of the sand will spill out.
Hope this clarify your question. :)
Thks teacher.
ReplyDelete