Navat,+Oze

Coins and Chemistry Oze Navat

I found it interesting that coins are made to be worth less then there face value, so that its not worth less then the metal itself. I never really thought about it that way, but it is very smart and makes sense. I use to collect coins as a kid and I use to like how all coins were made out of different metals. I never knew about alloys, thats a good idea so make the coin stronger so that it doesnt wear and tear as easily. I thought that pennys were made out of all copper, and I was suprised to learn that there is also so zinc and tin made out of the coin too.

Oze, OK. Check your sentence structure and word choices. 5 stars. MW

Redefining The Kilogram

I thought it was interesting that one of SI base unit is an actual physical artifact and that all the others are physical properties of nature. I would think that all of the units would be set in stone, and they could not change. I was surprised that there is a big debate on the kilogram just because it lost some weight, I think that that is making big deal out of nothing. SI base units is something we learned in class and its amazing to believe that something like the weight of something could matter so much and affect a lot in the world.

Oze, This lost mass has really caused a hubbub in the scientific community. 5 stars. MW

Motion Detectors

I have learned a lot from this article. A lot of people that I know and some of my neighbors have motion sensors for there driveways, I noticed them but never really could think of how they worked, now I understand how it works.I thought it was very interesting how it is something so simple as a light source aimed at a photo censor. I thought it was neat how infrared motion censors know what the temperature of things are so that they can be identiflied as human or not. When I read this article I think of cartoons where you see a bank heist and there are red lasers pointed everywhere to set off the alarms. I thought it was cool to learn that some animals like snakes can see some infrared along with regular colors to help them catch prey in the dark, I didnt know that.

Oze, Interestingly enough there are no actual banks or museums that use those visible red lasers for security - it's just a hollywood trick. 5 stars. MW