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## Middle school physics - NGSS

### Course: Middle school physics - NGSS>Unit 1

Lesson 1: Representing motion

# Units

The position and direction of motion an object has is described using units. In order to communicate this information scientists need to share which system of units they are using in order to understand the behavior of an object. Created by Khan Academy.

## Want to join the conversation?

• Why is it called SI units when 'SI' stands for International System? Shouldn't they be called IS units?
• SI actually stands for the French “système internationale”, and it just gets abbreviated that way in all languages.
• Why are their different units for the same thing. Like feet and inches? Why can’t we just use one?
• When people ask how old you are, stop telling them how many years old you are, start telling them how many days old you are.
• Are there other units in physics?
• yeah there's stuff like joules , newtons etc.
• She's a better drawer than I am
• I am literally in 3d grade and I am learning this stoff
• hi everyone
• She says that we all know how long a meter is, but Americans aren't taught the metric system in school - we're taught imperial. So how would an American know how long a meter is? We use inches, feet, yards, etc.
• A meter is about 3 feet of around a yard
(1 vote)
• I like to eat food
• everyone does
• I know American scientists use SI/metric, but I feel like if the U.S. was a person they'd be in the corner stifling their laugh at
• Why is it called SI units when SI stands for international system they should call it IS
• SI stands for Système Internationale, which is French
• what are the other units ?
• THE BASIC 7 SI UNITS:
meter(metre?)
mole(amout of substance)
kilogram
ampere(ele. currents)
Kelvin(temp.)
second
cd("storng-ness" of light)

hope that's useful! :)