Review:
Mass - How much matter an object has
- remains constant
- cannot be 0
- measured in kilograms (kg)
Weight - force of gravity on a object
- changes based on gravity
- measured in Newtons (N)

(F= force, M = Mass, A = Acceleration)

• ​Inertia is the property of an object that makes it resist changes in its motion.

• Objects want to keep doing what they're already doing.

• If something is at rest (not moving), it wants to stay at rest.
  

​If something is moving, it wants to keep moving in a straight line at the same speed.

Inertia and Mass:

• Inertia is related to an object's mass.

• Objects with more mass have more inertia.

• It's like they're "heavier" when it comes to resisting changes in motion.

• So, a big heavy truck has more inertia than a small toy car.

In space, where there's no air resistance or friction, objects keep moving in a straight line at a constant speed unless something else, like a spaceship's engines, changes their motion.

Inertia in Space

Inertia and Gravity work together in various ways to explain the motion of objects in the universe. Here's how they collaborate:

Orbital Motion: Gravity and inertia work together to keep smaller celestial bodies, such as planets, moons, and satellites, in orbit around larger objects like stars or planets.

Inertia and Gravity work together in various ways to explain the motion of objects in the universe. Here's how they collaborate:

• Gravity's Role: Gravity is the force of attraction between two masses. In the case of a planet orbiting a star, gravity pulls the planet toward the star.

Inertia and Gravity work together in various ways to explain the motion of objects in the universe. Here's how they collaborate:

• Inertia's Role: Inertia is the tendency of an object to resist changes in its state of motion. In this scenario, the planet's inertia wants it to keep moving in a straight line, tangential to its orbit.

Inertia and Gravity work together in various ways to explain the motion of objects in the universe. Here's how they collaborate:

• Balanced Forces: When gravity (magnetic force) pulls the planet toward the star, the planet's inertia (force of motion) keeps it moving forward. These forces balance each other, resulting in a curved path—the planet orbits the star instead of falling directly into it or drifting away into space.

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