#### what constitutes proof

Force

the push or pull of an object

Newton's first law of motion

an object will remain at rest unless acted upon by unbalanced force

Fact

an observation that has been repeatedly confirmed

Hypothesis

a tenative statement about the natural world

Theory

a well proven explanation of some aspect of the world

what does a theory incorporate?

laws, inferences and tested hypotheses

What are hypotheses used for?

to build more complex inferences and explanations

What happens to truth in science?

it may be modified or discarded, is never final

Wave frequency

the pitch of note, number of vibrations per second

resonance frequency

the specific note or pitch at which an object vibrates at

sympathetic vibration

when one object vibrates and causes another object to vibrate at the same frequency

What is the Tacoma narrows bridge an example of? (3)

resonance frequency, sympathetic vibration, wave frequency

Which is greater: force of buoyancy or force of gravity?

force of buoyancy

What is buoyancy?

the ability to float in water, air or another fluid

What is gravity?

the force that attracts an object to the center of the earth

How does bouyancy work?

if the combined density of two different objects is less, the one that is less will float up

Density

the degree of compactness of a substance

if one twin moved the speed of light and the other stayed on earth, the twin that moved the speed of light wouldn't have aged while he went fast

What happens when you go the speed of light?

time stops

What is science?

finding out what is real and accumlating that body of knowledge

What does it take for a scientist to believe something?

direct, personal observation, direct personal experimentation, information from a credible source, reporting in peer viewed journals