Smaller than the eye can see: How your computer is made June 19, 2006

Transcription

1 Smaller than the eye can see: How your computer is made June 19, 2006 Agenda for today: 1) Getting to know each other/taking pictures (Mark) 2) Overview of the next three weeks (Mark) 3) Keeping a laboratory notebook/quizzes (Marie) 4) Metric units of length and scientific notation (Keith) 5) Powers of 10 video making notes/answering questions (Marie) 6) Computer chip movie (Steve) 7) Powers of 10 activities (make sure to record your observations in your notebooks) Metric units of length 1000 m = 1 km 1000 mm = 1 m 1000 µm = 1 mm 1000 nm = 1 µm 100 cm = 1 m kilo = 1000 = 10 3 milli = = 10-3 micro = = 10-6 nano = = 10-9 centi = 0.01 = 10-2 Note: Micrometers are sometimes called microns

2 Powers of 10 activities: Meters (m) Measure the following objects in units of meters: your own height, the height of the room, the height of a desk, the width of the hallway, and at least one object of your own choice. How many meters are in a kilometer? What is your height in units of centimeters? Final comments on Nanometers (nm): Many objects in computers are measured in nanometers. For example, the smallest features on computer chips are currently about 200 nm in width. How many objects which are 200 nm long would you have lay end to end in order to get something as long as the width of your hair? Millimeters (mm) Measure the following objects in units of millimeters: the lines on your thumb (ink pad is available), the spacing between threads on a machine screw, and the length of a machine screw. How many millimeters are in a centimeter? What is the distance between two threads on the screw in units of micrometers? What is the smallest distance that you could accurately measure with your eye and a ruler? Micrometers (µm) Use the optical microscope to measure the following objects in units of micrometers: the diameter of a hair, the width of a mosquito leg, and if there is time some object of your own choice. How many of your hairs would you have to stack side-by-side in order to make a stack 1 m long? What is the smallest distance that you think you could measure accurately with this optical microscope?

3 (Put these pages in your notebooks) Metric units of length 1000 m = 1 km 1000 mm = 1 m 1000 µm = 1 mm 1000 nm = 1 µm 100 cm = 1 m kilo = 1000 = 10 3 milli = = 10-3 micro = = 10-6 nano = = 10-9 centi = 0.01 = 10-2 Note: Micrometers are sometimes called microns Observations in units of meters (m): My height is: The height of the room is: The width of the hallway is: (Provide measurements here for the object of your own choice.) Questions about meters (m) 1) How many meters are in a kilometer? 2) What is your height in units of centimeters? Questions about the video: 1) About how wide is the earth (in units of meters)? 2) About how wide is the United States (in meters)? 3) About how wide is the nucleus of an atom (in meters)? 4) How do you write 10 millimeters in units of meters using scientific notation?

4 Observations in units of millimeters (mm); The space between two lines on my thumb is: The spacing between threads on a machine screw is: The length of a machine screw is: Question about nanometers (nm): 1) The smallest features on computer chips are about 200 nm. How many objects which are 200 nm long would you have lay end to end in order to get something as long as the width of your hair? Questions about millimeters (mm): 1) How many millimeters are in a centimeter? 2) What is the smallest distance that you could accurately measure with your eye and a ruler? Observations in units of micrometers (µm) The diameter of a hair from my head is: Questions about micrometers (µm): 1) How many of your hairs would you have to stack side-byside in order to make a stack 1 m long? 2) What is the smallest distance that you think you could measure accurately with this optical microscope?

5 1) How many micrometers (µm) are in 5 km? 2) How many nanometers (nm) are in 1 mm? 3) The electron micrograph below shows portions of two electrical connectors on a computer chip. The electrical connectors are the large whitish objects. Note that the scale bar at the bottom tells you how big 2 µm is. If a human hair were also in this picture, would it be smaller or larger than the objects already in the picture?

6 4) Why do you think that the size of objects on a computer chip is important?