Microgravity

Definition

Microgravity is a condition in which objects appear to be weightless and experience very small forces of gravity. This occurs when an object is in free-fall or orbit, effectively creating a state of continuous free fall towards Earth.

5 Must Know Facts For Your Next Test

1. Microgravity occurs because objects in orbit are in a state of continuous free-fall towards Earth.
2. The gravitational force is not zero in microgravity; it's just very small compared to the gravitational force we experience on Earth's surface.
3. Newton’s Universal Law of Gravitation still applies under microgravity conditions, as the force between two masses never actually becomes zero.
4. In microgravity, uniform circular motion can be observed, where objects move around Earth or another celestial body in a stable orbit due to the balance between gravitational pull and inertia.
5. Astronauts experience microgravity on the International Space Station (ISS), allowing for experiments that are impossible under normal gravity.

Review Questions

• What causes microgravity and why do astronauts feel weightless?
• How does Newton's Universal Law of Gravitation apply to objects in microgravity?
• Why is the force of gravity never truly zero, even in a microgravity environment?

Related terms

Uniform Circular Motion: The motion of an object traveling at a constant speed along a circular path.

Newton's Universal Law of Gravitation: A law stating that every point mass attracts every other point mass by a force acting along the line intersecting both points; this force is proportional to the product of their masses and inversely proportional to the square of the distance between them.

Free-Fall: The motion of an object where gravity is the only force acting upon it.