PHYSICAL SCIENCE

LONG TEST REVIEWER

According to Eratosthenes, following explains why a vertical stick casts a shadow in Alexandria but not in Syene

The Sun is directly overhead in Syene while in Alexandria, it is only almost directly overhead.

The light rays coming from the sun are parallel, and the Earth is curved.

Sphere - the shape of the Earth according to ancient Greeks

Eratosthenes - ancient Greek philosophers computed for the circumference of the Earth

250,000 stadia - the circumference of the Earth according to Eratosthenes’ computations

Geocentrism - theory of the structure of the solar system (or the universe) in which Earth is assumed to be at the center of it all.

Eclipse - An obscuring of the light from one celestial body by the passage of another between it and the observer or between it and its source of illumination.

Waxing Crescent

Third quarter

Waxing crescent

Astronomy - the branch of physical science dealing with heavenly bodies.

29.5 - How many days is it from one full moon to the next full moon?

Babylonian and Egyptian civilizations used a primitive version of a sundial, called Gnomon, in systematically observing the motion of the sun

Mercury - the nearest planet from the Sun

Johannes Kepler - Brahe's most famous student

The great contribution of Tycho Brahe was to observe planetary positions with sufficient accuracy so that Kepler could later use the data to discover the laws of planetary motion

Statement of Kepler's first law - Planets move along an elliptical path with the Sun at one of the foci.

the laws formulated by Kepler using Brahe’s data and observations -Law of Ellipses,Law of Equal Areas and Law of Harmonies

Galileo observe the sunspots, the phases of Venus, and the craters on the moon In natural motion, an object will move and will eventually return to its natural state depending on the composition that the object is made of.

Galileo believed that a projectile is a combination of uniform motion in the horizontal direction and uniformly accelerated motion in the vertical direction. Objects dropped simultaneously will reach the ground at the same time regardless of their masses and air resistance.

Galileo used an inclined plane to perform his experiments both on uniformly accelerated motion and to study projectile motion. Rolling ball is an example of horizontal motion. A ball rolling down in an inclined plane increases its speed by different value after every second

The gravity of earth surface is 9.8m/s².

According to Galileo, free- fall undergoes constant acceleration

In Galileo's experimentation using two different weights of ball dropping in the leaning Pisa tower, he proves that heavier and lighter object fall at the same time if there is no air resistance.

He also measures the acceleration

Motion is constantly changing