Have You Ever Wondered?
Thanks to gravity, we have our feet firmly on the ground. Without gravity, we might float right into outer space and never be seen again. Instead, Earth pulls us toward its center at all times, keeping us on the ground.
Every object with mass has a gravitational pull on the objects around it. That force depends upon the masses of the objects. Things with a lot of mass, such as Earth, exert a strong gravitational pull on the objects near it, such as you and me.
Air resistance: Air is all around us. Those air molecules push against each other and other objects. They provide an upward force of friction against falling objects. Galileo also discovered that objects that are more dense are affected less by air resistance, while objects that are less dense will be slowed down more by air resistance.
This explains why a feather will fall to the ground very slowly when dropped. On the other hand, a brick will fall quickly to the ground as if there was no air around it. Scientists who have tested these theories will tell you that, if you drop a feather in a vacuum (a container with no air), it will fall at the same rate as the brick!
- How fast can a feather fall?
- At what rate do objects fall toward Earth?
- Why do different objects take different times to fall to Earth from a particular height?
Thanks to gravity, we have our feet firmly on the ground. Without gravity, we might float right into outer space and never be seen again. Instead, Earth pulls us toward its center at all times, keeping us on the ground.
Every object with mass has a gravitational pull on the objects around it. That force depends upon the masses of the objects. Things with a lot of mass, such as Earth, exert a strong gravitational pull on the objects near it, such as you and me.
Air resistance: Air is all around us. Those air molecules push against each other and other objects. They provide an upward force of friction against falling objects. Galileo also discovered that objects that are more dense are affected less by air resistance, while objects that are less dense will be slowed down more by air resistance.
This explains why a feather will fall to the ground very slowly when dropped. On the other hand, a brick will fall quickly to the ground as if there was no air around it. Scientists who have tested these theories will tell you that, if you drop a feather in a vacuum (a container with no air), it will fall at the same rate as the brick!