Forces and Gravitational Forces Notes

Force

• Definition: A push or pull on an object.

Gravitational Force (Gravity)

• Definition: Force of attraction between two objects.
• Example: Planets orbit the Sun due to gravity.
• The moon has $1/6$ the mass of the Earth, which means $1/6$ the gravitational pull.

Air Resistance

• Definition: Opposite force caused by air against a moving object.
• Drag is air resistance horizontally.

Mass

• Definition: The amount of matter in an object.

Weight

• Definition: Response of mass to the pull of gravity.
• Formula: $Weight = mass * gravitational\ pull$
• Weight changes with location; weighs less on the Moon.

Direct Relationship

• Definition: When both factors increase together or decrease together.
• $mass \uparrow$ $gravitational\ pull \uparrow$
• $friction \uparrow$ $speed \uparrow$

Indirect Relationship

• Definition: When one factor increases, the other decreases visa versa.
• $mass \uparrow$ $gravitational\ pull \downarrow$
• $distance \uparrow$

Planets in Order (starting closest to the sun):

• Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune