4 Physical Science Gravity

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WHAT IS GRAVITY? Have you ever wondered why things fall? It's because of me! GRAVITY! Nothing in the universe can escape my grasp!

All objects attract one another. This force is called gravity. A force is something that pushes or pulls an object. Gravity is the force that keeps your feet on the ground. If there were no such thing as gravity... ...you would fly up into the air and off into space. How can I be so powerful?!

The strength of gravity depends on two things: distance and mass. Distance is the space between two objects. The farther apart two objects are from each other, the weaker the pull of gravity between them. Mass measures how much matter an object holds. Everything is made of matter. The more mass an object has, the more it pulls on objects around it. Gravity!

All objects have gravity- even you! Your body's gravity pulls Earth toward you. But Earth has trillions and trillions times more mass than you do. Earth's gravity pulls you toward the ground. That's why you can only jump so high!

MEASURING GRAVITY Gravity is an invisible force, but we can still measure it. Weight is a measure of the pull of gravity on an object. You've probably weighed things to find out how heavy they are. When we weigh things to find out their mass, we use pounds or kilograms as units of measurement.