Weight

Weight is how heavy something feels. It depends on gravity. Gravity is the force that pulls things down toward the Earth. We measure weight with a scale. The more mass something has, the more gravity pulls on it.

How We Measure Weight

People use scales to measure weight. In the United States, weight is often measured in pounds and ounces. Other countries use grams and kilograms for both mass and weight. Doctors weigh babies at birth. Grocery stores weigh fruit so you know the price.

Weight in Space

Your weight can change if gravity changes. On the Moon, gravity is much weaker. A kid who weighs 60 pounds on Earth would weigh only 10 pounds on the Moon. In outer space, far from any planet, you would feel weightless. That is why astronauts float inside their ships.

Fun Facts

• The heaviest animal on Earth is the blue whale.
• Elephants can weigh more than 10,000 pounds.
• On Jupiter, you would weigh about 2.5 times as much as on Earth.

Did You Know?

Astronauts on the space station are falling around the Earth, which is why they feel weightless.