Gravity Study Flashcards

Flashcards about Gravity

Gravitational Force

Attractive, non-contact force between objects with mass.

Orbit

The path an object follows around another due to gravity.

Acceleration Due to Gravity

9.8 m/s² (on Earth). Unit: meters per second squared (m/s²).

Mass

Amount of matter, does not change. Unit: kilograms (kg).

Weight

Force of gravity, changes with location. Unit: Newtons (N).

Formula for Weight Calculation

W = mg → Weight = Mass × Gravity, Units: Newtons (N) = kilograms (kg) × meters per second squared (m/s²).

Air Resistance

A force that opposes the motion of objects as they move through the air. It slows down objects, especially lightweight and wide-surface objects like feathers or parachutes.

Objects Affected by Air Resistance

Feathers, paper, parachutes (more affected due to large surface area & lightweight), Rocks, metal balls, dense objects (less affected due to compact shape & heavy).

Factors Affecting Gravity Strength

Mass & Distance → More mass = stronger gravity, greater distance = weaker gravity.

Newton’s Gravity Discoveries

Gravity governs planetary motion; mass & distance determine gravitational strength.

Why Do Objects Fall at the Same Rate?

Gravity affects all objects equally, regardless of mass (if no air resistance).

Strength of Gravitational Fields

Decreases with distance.

Gravitational Field Model Purpose

Predicts the strength and direction of non-contact forces on objects.

Force Fields

Models the force an object would experience at any location in space.

Difference Between Magnetic, Static, and Gravitational Forces

Gravity only attracts. Magnetic & static forces can attract or repel.

Examples of Gravity in Action

Objects in space orbit due to gravity. The moon follows Earth's gravitational pull. Earth pulls objects toward its center.

How Weight Changes in Space

Weight decreases on planets with less mass than Earth. Weight increases on planets with more mass than Earth.

How Would Gravitational Field Lines Look Near Earth?

Closer arrows near Earth = stronger field. Farther apart arrows as distance increases = weaker field.

Newton’s Evidence of Gravity

Observed planetary orbits and patterns, leading to gravity models.

Free Fall Tower Gizmo

Shows how gravity affects falling objects. Objects of different masses fall at the same rate unless air resistance interferes. Gravity is the only force acting in free fall (ignoring air resistance).

Gravity & Force PhET Simulation

Demonstrates how mass and distance affect gravitational force. More mass = stronger gravity. More distance = weaker gravity.

Which is the weakest gravitational force, assuming that the distances between the 2 objects are

the same. (highlight the correct answer)

a. The gravitational force between 2 planets the size of earth

b. The gravitational force between a squirrel and an acorn

c. the gravitational force between a person and the earth

Explain your reasoning.

b because gravity depends on mass—larger mass means stronger gravitational force.

• Two Earth-sized planets have enormous mass, creating strong gravity.

• A person and Earth also have noticeable gravity, because Earth has massive size.

• A squirrel and an acorn have very small masses, making their gravitational force extremely weak.

5. Which situation demonstrates the strongest gravitational force? a. An astronaut standing on the earth b. An astronaut floating outside a space station in the earth atmosphere c. An astronaut floating outside a space station out of the earth’s atmosphere. Explain your reasoning.

• The closer an object is to a massive body (like Earth), the stronger the gravitational pull.

• An astronaut standing on Earth experiences Earth's full gravitational force (9.8 m/s²), making it the strongest gravitational interaction in this scenario.

• An astronaut floating outside the space station in Earth's atmosphere is still affected by Earth's gravity but slightly less than someone standing on the ground.

• An astronaut floating farther away, out of Earth's atmosphere, experiences weaker gravity because they are farther from Earth’s center, meaning Earth's pull decreases with distance.