What does a atom weigh?

An atom is so small that normal measurement units like "grams" or "ounces" don't really make sense. You can use them, but it's like trying to measure the length of your cat in kilometers; you end up with a very tiny number that's hard to picture. Scientists actually use a special unit called the "atomic mass unit" (shortened to u) to measure atoms. So for instance one Carbon atom is 1u, and a heavier Uranium atom is about 238u.

Can anyone explain me these units like pounds, ounces, yards and gallons? I only know the metric system. We don't use these other units in India.

These are all units part of the Customary System in the United States, also known as the Imperial System by people who use the metric system. Khan Academy is originally an American company, so they use this system. Pounds and ounces are kind of like grams and kgs in other countries. They are used to measure weight and mass. 16 ounces make a pound, and 2,000 pounds make a ton (not to be confused with tonne, which is in the metric system). Yards, inches, miles, and feet are kind of like meters and centimeters. They are used to measure distance. 12 inches equal to one foot, 3 feet are equal to one yard, and 5280 feet, or 1760 yards. Gallons, pints, cups, and fluid ounces (not to be confused with regular ounces) are used to measure volume, kind of like liters (litres) and milliliters (millilitres). 2 cups equal one pint, 2 pints equal one quart, and 4 quarts equal 1 gallon. For more information, you can use the google converter tool to help.

does a truck weigh 2 tons or 2.5 tons? (note that 2.5 is 5/2 or 2 1/2).

it is 2 1/2 and 5/2 because say 1 is 2/2 so 4/2 is 2 and add 1/2 to 4/2 = 5/2 = 2 1/2 do you get me? if so happy to help.

Are lb heavier then kilograms?

No. A pound (lb) is about 454 grams, while a kilogram is 1,000 grams. So actually a kilogram is heavier than a pound (on Earth's surface). Have a blessed, wonderful day!

Main content

4th grade

Course: 4th grade > Unit 14

Lesson 1: Estimating mass

Choose pounds or ounces to measure weight

Name: Choose pounds or ounces to measure weight
Uploaded: 2013-10-23T13:37:58Z
Description: Sal discusses US customary units of mass or weight such as ounce, pound, and ton.

CCSS.Math:

4.MD.A.1

Google Classroom

Sal discusses US customary units of mass or weight such as ounce, pound, and ton. Created by Sal Khan.

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KBenjamin
Posted 8 years ago. Direct link to KBenjamin's post “What does a atom weigh?”
What does a atom weigh?
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(14 votes)
Answer
- carrollalexp
  Posted 7 years ago. Direct link to carrollalexp's post “An atom is so small that ...”
  An atom is so small that normal measurement units like "grams" or "ounces" don't really make sense. You can use them, but it's like trying to measure the length of your cat in kilometers; you end up with a very tiny number that's hard to picture. Scientists actually use a special unit called the "atomic mass unit" (shortened to u) to measure atoms. So for instance one Carbon atom is 1u, and a heavier Uranium atom is about 238u.
  Comment on carrollalexp's post “An atom is so small that ...”
  (17 votes)
Rashik
Posted 6 years ago. Direct link to Rashik's post “Can anyone explain me the...”
Can anyone explain me these units like pounds, ounces, yards and gallons? I only know the metric system. We don't use these other units in India.
Button navigates to signup pageComment on Rashik's post “Can anyone explain me the...”
(9 votes)
Answer
- Orna Mukhopadhyay
  Posted 6 years ago. Direct link to Orna Mukhopadhyay's post “These are all units part ...”
  These are all units part of the Customary System in the United States, also known as the Imperial System by people who use the metric system. Khan Academy is originally an American company, so they use this system. Pounds and ounces are kind of like grams and kgs in other countries. They are used to measure weight and mass. 16 ounces make a pound, and 2,000 pounds make a ton (not to be confused with tonne, which is in the metric system). Yards, inches, miles, and feet are kind of like meters and centimeters. They are used to measure distance. 12 inches equal to one foot, 3 feet are equal to one yard, and 5280 feet, or 1760 yards. Gallons, pints, cups, and fluid ounces (not to be confused with regular ounces) are used to measure volume, kind of like liters (litres) and milliliters (millilitres). 2 cups equal one pint, 2 pints equal one quart, and 4 quarts equal 1 gallon. For more information, you can use the google converter tool to help.
  Comment on Orna Mukhopadhyay's post “These are all units part ...”
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lol
Posted 3 years ago. Direct link to lol's post “does a truck weigh 2 tons...”
does a truck weigh 2 tons
or 2.5 tons?

(note that 2.5 is 5/2 or 2 1/2).
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(5 votes)
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- Mark the Pi Jedi
  Posted 3 years ago. Direct link to Mark the Pi Jedi's post “it is 2 1/2 and 5/2 becau...”
  it is 2 1/2 and 5/2 because say 1 is 2/2 so 4/2 is 2 and add 1/2 to 4/2 = 5/2 = 2 1/2 do you get me? if so happy to help.
  Comment on Mark the Pi Jedi's post “it is 2 1/2 and 5/2 becau...”
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Do they have questions for each single vid? I’m so confused🧐
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- THE GHOST MATHEMATICIAN
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Are lb heavier then kilograms?
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- Ian Pulizzotto
  Posted 4 years ago. Direct link to Ian Pulizzotto's post “No. A pound (lb) is abou...”
  No. A pound (lb) is about 454 grams, while a kilogram is 1,000 grams. So actually a kilogram is heavier than a pound (on Earth's surface).
  
  Have a blessed, wonderful day!
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up vote me i up vote u
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how many pounds does our sun weigh?? :1
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how much does 10 atoms weigh
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How much does a human weigh in oz?
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Video 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.