Part A: What is the radius of a CD?
Part B: What is the height of the CD?
Part C: What is the volume of the CD?
Part D: Measure the radius in the center of the CD to the beginning of the music area. Find the volume after.
Part E: What's the volume for music? Subtract your answer from Part D from the answer to Part E.
Part 3B: How many minutes of music are on the CD? How many minutes are stored in each cubic centimeter of volume?
Please answer ! I don't understand how to do it . I will give 10 points depending on how good your answer is . Please explain ! Thanks .
Part B: What is the height of the CD?
Part C: What is the volume of the CD?
Part D: Measure the radius in the center of the CD to the beginning of the music area. Find the volume after.
Part E: What's the volume for music? Subtract your answer from Part D from the answer to Part E.
Part 3B: How many minutes of music are on the CD? How many minutes are stored in each cubic centimeter of volume?
Please answer ! I don't understand how to do it . I will give 10 points depending on how good your answer is . Please explain ! Thanks .
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It's really straight forward. You measure the radius (distance from the center of the CD to the outside) and the height (measure the thickness of the CD) then you find the area of the CD's surface by multiplying the radius by itself then multiplying your answer times 3.14 or pi (a= (pi)r^2) then when you've found that you multiply it by the height of the CD and you've found the volume. To find how many minutes of music there are you simply find the length of all the music on the CD and you divide that by the volume of the CD.
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OK...if you're going to measure with a cm ruler you're introducing systematic error because of the crudeness of your measuring system. Industry standards dictate the thickness and radius of these little jewels..see http://www.dimensionsguide.com/compact-d…
You'll have to convert to cm from mm but that's just dividing mm/10 = cm.
Part D will be your key. I'd use a metric caliper to measure and subtract from the radius you get from the website.
Now you can use the formula that queen gave for finding the volume and there is a standard number of minutes you can record on a CD...it's in the same site above.
If your instructor is looking for approximations using just a ruler then you need to do it his/her way....but if you want a much more exact answer get the standards, use a caliper and the volume formula and you can also determine min/cc from that.
You'll have to convert to cm from mm but that's just dividing mm/10 = cm.
Part D will be your key. I'd use a metric caliper to measure and subtract from the radius you get from the website.
Now you can use the formula that queen gave for finding the volume and there is a standard number of minutes you can record on a CD...it's in the same site above.
If your instructor is looking for approximations using just a ruler then you need to do it his/her way....but if you want a much more exact answer get the standards, use a caliper and the volume formula and you can also determine min/cc from that.
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Music is not written inside the vast majority of the volume of the CD. It is scripted underneath the label on an extremely thin layer of aluminum and acrylic, forming tiny bumps in a spiral pattern that can be detected by a laser, which "reads" the bumps so that the CD may be played. What you're really looking for is the length of the track of bumps, which, if you could lift the data track off a CD and stretch it out into a straight line, it would be 0.5 microns wide and almost 3.5 miles (5 kilometers) long.