Transcript File
FORCE & MOTION *A FORCE IS A PUSH OR PULL EXERTED BY ONE OBJECT ON ANOTHER. *EVERY FORCE HAS A DIRECTION. * MOTION IS WHEN AN OBJECT MOVES. *THE AGENT IS THE OBJECT APPLYING THE FORCE. *THE RECIEVER IS THE OBJECT RECEIVING THE FORCE. *A FORCE MAY BE BALANCED OR UNBALANCED. *A BALANCED FORCE IS WHEN THE FORCE BEING APPLIED TO AN OBJECT IS EQUAL TO THE FORCE BEING EXERTED BACK BY THE OBJECT. *AN UNBALANCED FORCE IS WHEN ONE FORCE IS GREATER THAN THE OTHER FORCE. CAUSING ONE OBJECT TO MOVE, STOP, OR CHANGE DIRECTION. KINDS OF FORCES 1). BUOYANT FORCE IS THE UPWARD FORCE EXERTED BY A FLUID ON AN OBJECT IMMERSED IN IT. 2). MAGNETIC FORCE A FORCE EXERTED ON OBJECTS THAT MAGNETIC PROPERTIES. 3). ELECTRICAL FORCE IS A FORCE EXERTED BY CHARGED PARTICLES OF AN OBJECT. 4). GRAVITATIONAL FORCE IS THE FORCE EXERTED BY ALL OBJECTS THAT PULL THE OBJECTS TOWARDS EACH OTHER. THE GRAVITATIONAL FORCE OF OBJECTS DEPENDS ON THE OBJECTS MASSES AND HOW CLOSE THE OBJECTS ARE TO EACH OTHER. 5). ELASTIC FORCE IS THE FORCE EXERTED BY OBJECTS THAT STRETCH. 6). FRICTIONAL FORCE IS THE FORCE EXERTED BY TWO OBJECTS THAT RUB AGAINST EACH OTHER. FRICTIONAL FORCE CAUSES HEAT. 7). CENTRIPETAL FORCE IS THE FOR EXERTED ON AN OBJECT TRAVELING IN A CIRCULAR PATTERN. THE FORCE IS PULLING THE OBJECT TOWARDS THE CENTER, OR MIDDLE OF THE CIRCLE. NEWTON’S LAWS OF MOTION ISAAC NEWTON DEVELOPED THEORIES ABOUT MOTION AS WELL AS OTHER SCIENTIFIC QUESTIONS. EVENTUALLY, HIS THEORIES WOULD BE PROVEN AND BECAME LAWS. NEWTON’S 1ST LAW OF MOTION * SAYS: THAT AN OBJECT AT REST OR IN MOTION WILL REMAIN AT REST OR IN MOTION, UNLESS ACTED UPON BY AN OPPOSITE FORCE. * NEWTON EXPLAINED THAT OBJECTS RESIST ANY CHANGE IN ITS MOTION. * INERTIA IS THE RESISTANCE OF MATTER TO CHANGE ITS MOTION. EXAMPLE: IF YOUR ON A MOTOR CYCLE AND IT HITS A WALL, THE MOTORCYCLE COMES TO A STOP. BUT YOUR BODY, WHICH WAS IN MOTION WITH THE MOTORCYCLE, RESISTS STOPPING AND CONTINUES IN MOTION. NEWTON’S 2ND LAW OF MOTION *SAYS: THE CHANGE IN MOTION OF AN OBJECT DEPENDS ON THE OBJECTS MASSES, AND THE SIZE OF THE FORCE EXERTED ON THE OBJECT. EXAMPLE: A LARGE LINEBACKER, TACKLES A SMALLER RUNNING BACK. THE LINEBACKER HAS MORE MASS AND IS ABLE TO EXERT MORE FORCE, THUS PUSHING THE RUNNING BACK BACKWARDS EASILY. NEWTON’S 3RD LAW OF MOTION *SAYS: FOR EVERY ACTION THERE IS AN EQUAL AND OPPOSITE REACTION. EXAMPLE: IF YOU FIRE A CANNON OR A GUN, THE FORCE OF THE CANNON PUSHES OUT ON THE CANNON BALL AND THE CANNON BALL PUSHES BACK ON THE CANNON, PROPELING IT BACKWARDS. * BECAUSE OF NEWTON’S CONTRIBUTIONS TO FORCE, FORCE IS MEASURED IN NEWTONS. (N) 100 GRAMS (g) OF MASS EQUALS 1 NEWTON (N) *HOW TO CHANGE POUNDS (lbs) TO NEWTONS (N) * HOW TO CHANGE NEWTONS TO POUNDS EXAMPLES: 10 lbs = 44.48 N 10 LBS X 4.448 = 44.48 N POUNDS (lbs) x 4.448 = NEWTONS NEWTONS X .225 = POUNDS 10 N = 2.25 lbs 10 N X .225 = 2.25 lbs *MOMENTUM IS ALSO CAUSED BY FORCE MOMENTUM IS DETERMINED BY MEASURING AN OBJECTS MASS ANDE MULTIPLYING IT BY ITS VELOCITY. (MOMENTUM (p) = m Xv EXAMPLE: A SEMI TRUCK AND A MOTORCYCLE ARE BOTH TRAVELING DOWN THE HIGHWAY AT 60 mph, THE SEMI TRUCK HAS MORE MOMENTUM BECAUSE IT HAS MORE MASS. OR: TWO SEMI TRUCKS THE SAME MASS TRAVELING DOWN THE HIGHWAY, BUT ONE TRUCK IS ONLY GOING 50mph AND THE OTHER TRUCK IS GOING 60 mph. THE TRUCK GOING 60 mph HAS MORE MOMENTUM, BECAUSE IT HAS MORE VELOCITY.