William W. answered • 10/13/21
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The key is that they list the mass in nanograms. To use W = mg, if you are going to use g = 9.8m/s2, you must use the mass in kg. Convert 1.67 x 10-15 ng into kg and you will get 1.67 x 10-27 kg
W = (1.67 x 10-27 kg)(9.8 m/s2) = 1.64 x 10-26 Newtons
William W.
You convert to kg because Newtons is defined as kg*m/s^2. Kg is also the standard SI unit just like m (meters) or s (seconds). The acceleration due to gravity is 9.8 m/s^2 and we need kg to multiply to give N.
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10/15/21
Bri S.
Oh ok, that makes sense. I know I have to convert something since the mass was in ng but I wasn't sure what unit to change it to. So is there a reason why we convert ng to kg instead of another unit like g or lbs? Is it because g is in m/s?10/15/21