About this video
The video sorts four objects by the best unit to measure their weight: pounds or ounces. Heavy things like an adult (about 160 pounds) or a kitchen table use pounds, while light things that weigh less than a pound, like a slice of bread or a pack of gum, use ounces.
You'll be able to
- choose pounds for heavier objects and ounces for objects lighter than a pound.
- use a known weight, like my own, to estimate other objects' weights.
Key words
- pound
- A US unit of weight for heavier things; an adult weighs many pounds.
- ounce
- A US unit of weight for light things that weigh less than a pound.
- reasonable
- Sensible; a unit that fits the size of what you measure.
Transcript
Identify the most reasonable units to measure the weight of the choices below. So we have an average adult, a slice of bread, a kitchen table, or a pack of gum. So I am an average adult, and I know that I weigh about 160 pounds. So I know that pounds are a pretty good measurement for about something the weight of an adult.
So I'll put adults in that category right over there. Now we have a single slice of bread. So even a full loaf of bread doesn't weigh a lot. Maybe that gets close to a pound, but a slice of bread is going to be less than a pound. So I would do this in ounces. A kitchen table.
Well, a kitchen table kind of weighs the same-- it could, if it's a very large kitchen table, could weigh the same or more than an adult. So I would do this in pounds. And then a pack of gum. So once again, a pack of gum is fairly light. If you've ever been to the gym and held even a 1-pound or 2-pound weight, it weighs more than a pack of gum.
So a pack of gum is going to be less than a pound, so ounces seem to make sense here.
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