PSC 1121: Physical Science

Definition study guide for PSC 1121

science

systematic knowledge accumulated in our effort to answer questions

pseudoscience

claims presented so that the appear to be scientific even though they lack supporting evidence and plausibility

theory

collection of laws that can be tested and proved, tested and disproved, or untested

vector

straight piece of a line with beginning and end

impulse

a force acting on an object for a period of time

energy

another way to review motion and the possibility to move

elastic collision

no energy turned to heat

inelastic collision

some energy is lost to heat

completely inelastic collision

all energy is turned to heat

work

mediator of one form of energy to another

power

how fast you work

center of mass

the average position of all the mass that makes up the object

center of gravity

the average position of weight distribution

torque

the tendency of a force to cause rotation

Kepler’s First Law of Gravity

The planets orbit the Sun in ellipses with the Sun at one focus

Kepler’s Second Law of Gravity

The line joining the Sun and the planet sweeps out equal areas in equal times

Kepler’s Third Law of Gravity

The period of the planet and the size of the ellipse relate

Steps of the Scientific Method

1. Observe

2. Hypnotize

3. Experiment

4. Conclude

Theory of Everything

the idea that all things can be explained through science

Equation for Kinetic Energy

KE = (1/2)mv²

Equation for Potential Energy

PE = mhg

Equation for Momentum

p=mv

Equation for Impulse

F x t

Four Fundamental Forces

• Electro-magnetic

• Weak Interaction

• Strong Interaction

• Gravitation

The shapes the force of gravity can create

• straight line

• circle

• ellipse

• parabola

• hyperbola

Unit for Momentum

(kg x m)/s

Unit for Impulse

N x s

static equilibrium

forces cancel each other

Unit of Energy

Joule

Newton’s First Law of Motion

Law of Inertia – an object at rest will stay at rest and an object in motion will stay in motion unless acted upon by a force

Newton’s Second Law of Motion

The acceleration of an object depends on the object’s mass and the amount of force applied

Newton’s Third Law of Motion

Every action has an equal opposite reaction

Equation for Force

F=ma

Equation for Centripetal Force

F_c=mv²/r

Law of Conservation of Momentum

momentum remains the same in a system – the amount of momentum at the beginning has the same momentum at the end