PHYS 100 Midterm

Definition- A statement about the world that competent observers who have made a series of observations agree on. -May change with time -For ex. Although it was once a fact that the universe is unchanging and permanent, today it is a fact that the universe is expanding and evolving

Fact

Definition- An educated guess; a reasonable explanation of an observation or experimental result that is not fully accepted as factual until tested over and over again by experiment. -Must be repeatedly tested to be accepted as factual -When a hypothesis has been tested over and over again and has not been contradicted, it may become known as a law or principle -Cardinal rule in science is that all hypotheses must be testable, or susceptible at least in principle, to being shown to be wrong

Hypothesis

Definition- The property of things to resist changes in motion Galileo's concept at first (ball experiment) but restated by Newton's first law -When the plane is horizontal, the ball should not lose any speed -In the absence of retarding forces, the tendency of the ball is to move forever without slowing down -This idea imagines motion without friction, discredits Aristotle theory of motion -Inertia is scalar

Intertia

Definition- A general hypothesis or statement about the relationship of natural quantities that has been tested over and over again and has not been contradicted. (Also known as a principle) -Might need to change if applied under new circumstances -When a hypothesis has been tested over and over again and has not been contradicted, it may become known as a law or principle

Law

Every object continues in a state of rest or of uniform speed in a straight line unless acted on by a nonzero net force -Key word is "continues", object continues to do whatever it was doing unless force exerted upon it, object at rest stays at rest -An object that is moving continues to move without turning or changing its speed -In the absence of net forces, a moving object tends to move along a straight-line path indefinitely -Ex. Bird sitting at rest at the top of a tall tree drops vertically to catch a worm on the ground, why isnt the worm swept by the moving earth? Inertia: not only is earth moving, but so are the trees, branches, and bird on the branch and world below. Things in motion remain in motion if no unbalanced forces are acting upon them. Also why you can jump next to a wall and the wall won't slam into you.

Newton's First Law: Law of Inertia

Definition- A synthesis of a large body of information that encompasses well-tested and verified hypotheses about certain aspects of the natural world. -NOT just an educated guess -Might still require revision over time -The theories of science undergo change and evolve as they go through stages of refinement/redefinition

Theory

Answer: 2 1 is NOT scientific hypothesis, no way to prove it wrong if no intelligent life is ever found.

Which is a scientific hypothesis? 1. Intelligent life exists on other planets somewhere in the universe 2. There is no other intelligent life in the universe

Answer: B

Which of the following is a scientific hypothesis? A) George Washington is the greatest American President. B) An oxygen nucleus contains more protons than a lead nucleus. C) The Universe contains an infinite number of stars, though many may never be observed. D) A red rose is more beautiful than a yellow rose.

Answer: 1. Human beings will never set foot on the moon is scientific because there is a test for wrongness. Even though incorrect, the statement is still scientific. 2. has no test for possible wrongness and 3. has no test for proving wrong because there could be another galaxy around the corner.

Which of the statements below is a scientific claim? 1. Human beings will never set foot on the moon 2. Some of the laws that govern nature cannot be detected by scientists 3. It is quite possible that in some other galaxy the laws of physics are fundamentally different than the laws we are acquainted with in this galaxy

Answer: A, because there is a test for falseness

Which of these if a scientific hypothesis? A) Atoms are the smallest particles of matter that exist B) Space is permeated with an essence that is undetectable C) Albert Einstein was the greatest physicist of the 20th century