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Hilda Said:

does anyone have the answers to the WATTS UP? science worksheet for 8th grade?

I bet if you hadn't wasted your time writing this, you would get that done faster.

Terry Said:

8th Grade Science Fair Project Ideas?

ohh i did this really cool thing were you put salt water in a glass container then put 2 iron electrodes in the salt water or steel wool if that's all you can get then you attatch 2 alligator clips on to the electrodes and the attatch the electrodes to the light bulb and the light bulb actually turns on.i has to do with the iron breaking down and it gives off a chemical reaction due to the oxyidation.
and i even gave you a link to were you can get all the supplies you need

Alvin Said:

CONVERSIONS 8th grade science test!! ~10 points~?

As billrussell42 said, use dimensional analysis. Using your example of cm/s to in/min, the need to convert both distance (cm to in) and time (sec to min) is apparent. Get those factors first and then assemble the conversion.
1 inch = 2.54 cm
60 seconds = 1 min

Now assemble and be sure the units divide out or "cancel":

(6 cm/s) x (1 in/2.54 cm) x (60 s/min) = 141.7 in/min
notice that cm and s divide out and you are left with in/min

If you have a document telling you that 6 cm/s is equivalent to 10 inches/min, then it's no wonder you are confused. That is incorrect.

Now suppose I didn't know 1 in. = 2.54 cm, but I know 1 foot = 0.3048 meters (which incidentally is the one you want to remember because it's the basal factor for SI to Imperial distance conversion. In 1958 the United States and countries of the Commonwealth of Nations defined the length of the international yard to be 0.9144 metres. Consequently, the international foot is defined to be equal to 0.3048 metres).
1 ft = 0.3048 m
12 in = 1 ft.
1 m = 100 cm
60 s = 1 min

Now assemble:

(6 cm/s) x (1 m/100cm) x (1 ft/0.3048 m) x (12 in/ft) x (60 s/min) = 141.7 in/min
notice that cm, m, ft, and s divide out leaving in/min

Eric Said: