4th Grade Homework 10/27-10/31
HOMEWORK ROOM 108 Fourth Grade MRS. KELLEY Week of 10/27-10/31/2014
MONDAY- Read p. 21Complete 1-9
TUESDAY- See Technology Requirements **
WEDNESDAY- p. 22 10-23
THURSDAY- See Technology Requirements **
FRIDAY- Friday- p.22 18-31
TECHNOLOGY ** All tech. components should be completed by Saturday, November 1st at 5:00p.m.
IXL www.ixl.com Fourth Grade/Fifth Grade 40 minutes ( Try to focus on place value and decimals)
COMPASS www.thelearningodyssey.com Work in Math for 30 Minutes
Vocabulary thermal energy conduction conductor insulator convection current radiation
Due Friday, October 31st.
Read the article that continues on the back of this page.
What connections can you make between this article and what we read about in Science on Thursday? In other words, explain reasons why Mrs. Kelley may have chosen this article to pair with what we are reading in our Science Text. (Yes, you can take the book home if you need to.)
The Nobel Prize is the highest award a scientist can receive. Each year it is given out in different fields of science and the arts. A committee in Sweden votes on who deserves the award.
In addition, each winner receives a $1.1 million prize.
This year the award in physics went for a discovery of a new lightbulb. It was given to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura. In the 1990s they discovered blue light-emitting diodes. We call them simply LEDs.
LED lights can make bright lightbulbs. They are also found in flat-screen TVs and computers. Cellphone screens now use them. LEDs use much less electricity than other types of lights.
They Knew They Could Do It
One-fourth of our electricity use is from lights, said Olle Inganäs. He is on the committee that chose the Nobel Prize winner. “Having much more light for much less electricity is really going to have a big impact.”
The new Nobel award winners worked for years on blue LEDs. Red and green LEDs have been around since the 1960s. But no one could make white light. Blue LEDs can make white light when combined with red and green LEDs. Creating blue LEDs took about another 30 years.
“A lot of big companies really tried to do this and they failed,” said Per Delsing in Sweden. He is also on the Nobel committee. But these three scientists "tried and tried again and eventually they actually succeeded.”
LEDs Are Brighter And Better For The Environment
The achievement required the growth of high-quality crystals. They were used as semiconductors. The team grew the crystals from a semiconductor that produces blue light. Semiconductors allow electricity to flow between a conductor, such as copper, and an insulator, like glass.
The color depends on the energy applied to the crystals. The energy applied to these crystals creates ultraviolet and blue light.
LED bulbs use much less energy than traditional lightbulbs. The old bulbs you see are called incandescent. They use electricity to heat a thin metal strand inside the glass bulb. It is called a filament. It wastes energy by giving off both heat and light. Instead, LEDs change energy directly into light. They do not produce heat.
LEDs also avoid problems of fluorescent lights, which are long, thin lights. Many offices use them. They rely on mercury, which pollutes the environment when it is thrown away.
LED Technology Is Everywhere
LED technology now lights our cellphone screens and phone flashlights. Many homes use them as well. Even the twinkling lights put on Christmas trees are LEDs.
There also may be more uses in the future. Ultraviolet light kills bacteria. So blue LEDs could be used to make clean drinking water, Delsing said.
He said the invention benefits all humans.
Akasaki and Amano worked together at a university in Japan to make the discovery. Nakamura worked at a chemicals company in Japan. He improved upon the discovery by Akasaki and Amano.
Nakamura is now a professor at the University of California. He learned of his award in the middle of the night.