The force of attraction between any two objects with mass.

When the only force acting on an object is gravity.

A region of space where a mass experiences a gravitational force; a vector field with magnitude and direction.

Gravitational field strength or acceleration due to gravity.

The gravitational force acting on an object, given by $F = mg$.

1. $F = G \frac{m_1 m_2}{r^2}$ (Gravitational Force), 2. $F = m_1 a$ (Newton's Second Law), 3. $m_1 a = G \frac{m_1 m_2}{r^2}$ (Equate forces), 4. $a = G \frac{m_2}{r^2}$ (Solve for acceleration), 5. $g = G \frac{M}{r^2}$ (Replace $a$ with $g$, $m_2$ with $M$).

1. Identify the masses $m_1$ and $m_2$. 2. Measure the distance $r$ between their centers. 3. Use the formula $F = G \frac{m_1 m_2}{r^2}$ with $G = 6.67 \times 10^{-11} Nm^2/kg^2$.

1. Identify the planet's mass $M$ and radius $r$. 2. Use the formula $g = G \frac{M}{r^2}$ with $G = 6.67 \times 10^{-11} Nm^2/kg^2$.

1. Equate gravitational force to centripetal force: $G \frac{Mm}{r^2} = m\frac{v^2}{r}$. 2. Solve for $v$: $v = \sqrt{\frac{GM}{r}}$ where $r$ is the orbital radius.

1. Identify initial conditions (velocity, height). 2. Use kinematic equations with $a = g = 9.8 m/s^2$. 3. Solve for unknowns (time, final velocity, distance).

Mass: Amount of matter in an object. Weight: Gravitational force acting on an object.

Gravitational Force: The force of attraction between two masses. Gravitational Field: A region of space where a mass experiences a gravitational force.

Both decrease with the square of the distance, following an inverse-square law.

$G$: Universal gravitational constant. $g$: Gravitational field strength (acceleration due to gravity).

Gravitational potential energy: Energy due to position in a gravitational field. Kinetic energy: Energy due to motion. In orbit, these energies are constantly interchanging.

Newton's Law: F = G rac{m_1 m_2}{r^2}, calculates the force between two masses. Field Equation: g = G rac{M}{r^2}, calculates the gravitational field strength due to a single mass.