Gravity Affects Motion - Middle School Earth and Space Science

Weight decreases; mass stays constant. Weight depends on $g$; mass is an intrinsic property.

An attractive force between objects with mass. Gravity pulls all matter together, stronger for more massive objects.

Toward the planet’s center of mass. Gravity always pulls objects toward the center of spherical bodies.

About $9.8\ \text{N/kg}$ (about $9.8\ \text{m/s}^2$). This value means 1 kg experiences 9.8 N of gravitational force.

Motion when gravity is the only significant force. No other forces act, so objects accelerate purely due to gravity.

The same: $g$ downward. All objects fall at same rate regardless of mass in vacuum.

Parabola (curved downward due to gravity). Horizontal velocity stays constant while gravity curves path downward.

They are equal in magnitude. Newton's third law: forces always come in equal and opposite pairs.

Downward, toward Earth's center. Gravity always pulls toward the center of mass.

Gravity. Gravitational attraction provides the inward pull for circular motion.

Gravity causes the acceleration. Gravity provides the downward force for acceleration.

$19.6\ \text{N}$. Apply $W = mg$: $2 \times 9.8 = 19.6$.

$\frac{12}{9}\ \text{N}$. Force decreases by $r^2$: $F/3^2 = 12/9$.

Along the line joining them, toward each other’s centers of mass. Gravity always attracts, never repels.

Gravity. Gravity continuously pulls projectiles downward during flight.

Continuous free fall around a body due to gravity. Object falls toward center but horizontal velocity keeps it circling.

Gravity. Gravitational attraction provides inward force for circular motion.

Larger radius means lower orbital speed. Weaker gravity at larger distances requires slower speed to maintain orbit.

They are in continuous free fall with their spacecraft. Both astronaut and spacecraft fall together, creating apparent weightlessness.

Planetary scale (gravity is negligible at atomic scale). Gravity too weak to affect atoms but dominates large-scale motion.

Mainly the Moon’s gravity (with the Sun also contributing). Moon's gravity pulls ocean water, creating bulges as Earth rotates.

Continuous free fall around a body due to gravity. Object falls toward center but horizontal velocity keeps it circling.

Neither; both fall at the same rate. Without air resistance, all objects accelerate equally at $g$.

Mass. Mass is intrinsic; weight depends on local gravity.