Science Chapter 2 Test

Natural Motion

Motion thought by Aristotle to happen ‘on it’s own’, such as objects falling towards Earth or smoke rising.

Violent Motion

Motion caused by a force like pushing or pulling, according to Aristotle.

Aristotle

A greek philosopher who believed motion required a continuous force; his ideas dominated science for centuries. 

Galileo

A scientist who used experiments to study motion; showed that objects fall at the same rate regardless of mass. 

Motion

A change in an object’s position compared to a reference point.

Inertia

The tendency of an object to resist changes in its motion; objects at rest stay at rest, objects in motion stay in motion. Example: Soccer ball slows on grass but rolls farther on ice.

Friction

A force that resits motion when two surfaces rub against each other. Example: hands grip using fingerprints, swimmers slow down from the drag of water. 

Leaning Tower of Pisa

The site where Galileo is said to have tested falling objects or different masses. 

Force

A push or pull that an change an object’s motion.

Mass

The amount of matter in an object; not the same as weight.

Gravity

A force of attraction between objects that have mass; on Earth it pulls objects toward the center.

Density

How much mass it packed into a certain volume (mass per unit volume). 

Volume

The amount of space an object takes up.

Weight

The force of gravity acting on an object’s mass.

Push/Pull

Basic ways to apply a force to an object. 

Vector

A quantity that has both size (magnitude) and direction, such as velocity or force.

Equilibrium Rule

The idea that when forces are balanced, the net force equals zero and the object’s motion does not change.

Speed

How fast an object moves; distance traveled per unit of time. 

Acceleration

A change in velocity over time; can be speeding up, slowing down, or changing direction. Free fall near Earth = about 10 m/s² down.

Velocity

Speed in specific direction.

Free Fall

Motion under the influence of gravity alone, without air resistance.

Inclined Planes

Sloping surfaces (ramps) that make lifting or moving objects easier by spreading out the work.

Modern Science 

Science based on observation, experimentation, and evidence, not just reasoning (Galileo helped begin this shift). 

Static Equilibrium

When all forces on an object are balanced and the object is at rest. 

Net Force

The overall force acting on an object after all the individual forces are combined.

Aristotle vs. Galileo

Aristotle reasoned about natural (up/down) and violent motion; Galileo used experiments and introduced inertia.

Inertia & Mass

Inertia is resistance to changes in motion; mass measures inertia. Mass does not equal weight.

Equilibrium (ΣF=0)

No change in motion - either at rest or constant velocity in a straight line. 

Support/Normal Force

Upward push from a surface that can balance weight.

Friction

Opposes motion or attempted motion; direction opposite motion (or intended motion)

Speed & Velocity 

Speed = distance/time (scalar). Velocity adds direction (vector). Motion is relative to a frame. 

Speed Formula

v = d/t

Average Speed Formula

Avg.S = total distance/ total time

Acceleration Formula

a = final velocity - initial velocity/time

Free-Fall Acceleration Equation

g= 9.8 m/s²

Weight Equation

W= mg

Density Equation

p= m/V

What were Aristotle’s claims that Galileo later proved wrong?

The claim that heavy objects fall faster and motion required a continuous force. Example: A rolling ball stops because of friction, not because it ‘runs out of force’.

Mass is _____ while weight _____ with ______(Earth and Moon)

universal, changes, location

Support (Normal) Force

Upward force balancing an object’s weight on a surface. Example: book resting on table = table pushes back.

How did Aristotle reason/explain motion?

By classifying it as natural or violent motion.