also called Yam, Kumara

About
The sweet potato is a dense, starchy root vegetable that packs nearly half a pound into a single measuring cup.
Sweet potatoes have a bulk density of about 59 pounds per cubic foot (0.95 g/mL), which is just slightly less dense than liquid water. Because the root flesh is firm and holds substantial moisture, it fills volume with very little empty air space when mashed or tightly chopped. Its density is very similar to common white potatoes and other firm root vegetables like carrots. A typical medium-sized root provides roughly one cup of prepared cubes.
From Wikipedia
The sweet potato or sweetpotato is a dicotyledonous plant in the morning glory family, Convolvulaceae. Its sizeable, starchy, sweet-tasting, tuberous roots are used as a root vegetable, which is a staple food in parts of the world.
Read more on Wikipedia →Text from Wikipedia’s “Sweet potato” article, CC BY-SA 4.0.
One cup weighs
7.93 oz (225 g)
Quick answer
One US cup of sweet potato weighs about 7.9 ounces (225 g). This makes a packed cup roughly as heavy as a cup of granulated sugar.
Typical figures, the same ones every comparison on the site uses; real ones vary.
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