Aristotelian vs

ARISTOTELIAN VS. GALILEAN VIEWS OF MOTION

Aristotle’s Theory of Motion

• Objects made of an ‘earth’ material fall toward the center of the Earth.

  • They seek their natural place.

Key Points

• Heavy objects fall faster than light ones.

• Objects fall faster in air than in water.

• Objects can be moved away from their natural places through violent forces.

• There is no motion without an applied force.

Galileo’s Theory of Motion

• A marble rolling on a flat surface will continue rolling indefinitely due to inertia.

  • Inertia: the tendency of an object to resist changes in its state of motion.

Concepts of Motion

• When a marble rolls down an inclined plane, the distance covered relates to the square of time.

• The motion of a marble rolled down an inclined plane at a 90-degree angle equals that of a free-falling body.

• All objects fall with the same constant acceleration due to gravity.

Review Questions

1. Based on Aristotle's concept, why does a balloon rise when released?

2. Why does a falling object gain speed?

3. How do Galileo's ideas on falling objects differ from Aristotle's?

Speed

• Definition: Distance refers to the total length of the path traveled by an object.

• Rate of Motion: Speed is the distance covered over time.

Speed Calculation

• Speed formula:

  • speed (v) = distance traveled (d) / time of travel (t)

Average Speed Example

• A car traveled 240 km from Manila to Pangasinan in 4 hours. (Average Speed = 240 km / 4 hr = 60 km/h)

Problems to Solve

1. An airplane travels 1800 km at a speed of 800 km/h; find the time taken.

2. A cyclist travels at a speed of 7 km/h. How far will they travel in 2 hours?

3. A car travels 540 km in 6 hours; calculate speed.

4. John runs 100 m in 20.0 s; calculate speed.

5. Lauren walks 400 m in 125 s; calculate her speed.

6. A whale swims at 8.0 m/s for 17 s; find the distance traveled.

7. Jim travels at 18.0 m/s for 2.0 s; calculate distance.

8. A train travels at 16 m/s, covering 3200 m; find the time.

9. Calculate time for traveling 672 km at 96 km/h.

Velocity

• Definition: Velocity refers to how fast an object moves and in which direction.

• Constant speed results in constant velocity.

• Displacement: Straight-line distance from the initial to final position.

Velocity Calculation

• Velocity formula:

  • velocity (v) = displacement (d) / time (t)

Difference Between Speed and Velocity

• Speed: scalar quantity, indicates how quickly something is moving.

• Velocity: vector quantity, indicates speed and direction of an object’s movement.

Graphical Representation of Motion

• Analyze motion using position-time and velocity-time graphs.

Data Table for Context

• Displacement and Time Measurements for a cyclist moving North:

  • Displacement (m) and Time (s) for various intervals.

• Questions to explore based on graphical data: A. Plot displacement against time. B. Find average velocity. C. Find the slope of the graph. D. Interpret what the slope represents.