Newton's Laws: Elephant and Feather - Air Resistance
4 The Physical Setting
For Grades: 9-12
Learning Goal 1
The change in motion (direction or speed) of an object is proportional to the applied force and inversely proportional to the mass.
Learning Goal 2
All motion is relative to whatever frame of reference is chosen, for there is no motionless frame from which to judge all motion.
Learning Goal 3a
When electrically charged objects undergo a change in motion, they produce electromagnetic waves around them.
Learning Goal 3c
In empty space, all electromagnetic waves move at the same speed—the "speed of light."
Learning Goal 4
Whenever one thing exerts a force on another, an equal amount of force is exerted back on it.
Learning Goal 5ab
The observed wavelength of a wave depends upon the relative motion of the source and the observer. If either is moving toward the other, the observed wavelength is shorter; if either is moving away, the wavelength is longer.
Learning Goal 5c
Because the light seen from almost all distant galaxies has longer wavelengths than comparable light here on Earth, astronomers believe that the whole universe is expanding.
Learning Goal 6ab
Waves can superpose on one another, bend around corners, reflect off surfaces, be absorbed by materials they enter, and change direction when entering a new material. All these effects vary with wavelength.
Learning Goal 6c
The energy of waves (like any form of energy) can be changed into other forms of energy.
Learning Goal 7
In most familiar situations, frictional forces complicate the description of motion, although the basic principles still apply.
Learning Goal 8
Any object maintains a constant speed and direction of motion unless an unbalanced outside force acts on it.