Bell Ringer Sports announcers will occasionally say that a person is accelerating if he/she is moving fast. Why is this not an accurate description of what acceleration is? Sports announcers will occasionally say that a person is accelerating if he/she is moving fast. Why is this not an accurate description of what acceleration is?

Objectives Define acceleration in words and with an equation Define acceleration in words and with an equation Identify positive and negative acceleration by analyzing a graph Identify positive and negative acceleration by analyzing a graph Calculate acceleration with the use of an equation and graph Calculate acceleration with the use of an equation and graph Define and apply the force of gravity Define and apply the force of gravity

Change in Velocity Each time you take a step you are _________________ the _____________ of your body. Each time you take a step you are _________________ the _____________ of your body. You are probably most familiar with the velocity changes of a moving bus or car. You are probably most familiar with the velocity changes of a moving bus or car. The rate at which _________ (__________ or __________) changes occur is called _______________________. The rate at which _________ (__________ or __________) changes occur is called _______________________.

Acceleration= ________ ______ ________ ______ Acceleration= ________ ______ ________ ______ Change in velocity = final – starting velocity velocity Change in velocity = final – starting velocity velocity Acceleration= __________________________ Acceleration= __________________________

Acceleration = Velocity (final) - Velocity (original) time A car traveling at 60 mph accelerates to 90 mph in 3 seconds. What is the car’s acceleration? = = =

Acceleration = Velocity (final) - Velocity (original) time A car traveling at 60 mph slams on the breaks to avoid hitting a deer. The car comes to a safe stop 6 seconds after applying the breaks. What is the car’s acceleration? = = =

- A _________________ acceleration produces a __________ line or linear slope (_______________). - The ________ of a non- linear velocity-time graph (rise/run) will predict an objects instantaneous ____________________. a = / - A _________________ acceleration produces a __________ line or linear slope (_______________). - The ________ of a non- linear velocity-time graph (rise/run) will predict an objects instantaneous ____________________. a = / Calculate the instantaneous acceleration of the graph: a = v/t a =

Free fall The constant ___________________ of an object moving only under the force of _______________ is "g". The constant ___________________ of an object moving only under the force of _______________ is "g". The acceleration caused by ____________ is _____ m/s 2 The acceleration caused by ____________ is _____ m/s 2 If there was no _________, all objects would fall at the same ____________ If there was no _________, all objects would fall at the same ____________ Doesn’t depend on ____________ Doesn’t depend on ____________ After 1 second falling at 10 m/s After 1 second falling at 10 m/s After 2 seconds ________ m/s After 2 seconds ________ m/s 3 seconds _________ m/s 3 seconds _________ m/s

Galileo 1600’s 1600’s Studied how things fell Studied how things fell Didn’t have a good clock Didn’t have a good clock Rolled balls down an _______________ plane Rolled balls down an _______________ plane Found that the ___________ increased as it rolled __________ the ramp Found that the ___________ increased as it rolled __________ the ramp

Galileo t = 0 t = 1 second t = 2 seconds t = 3 seconds Acceleration= ____________________________

Galileo u Same things happen when things fall u Didn’t drop things from Tower of Pisa

Falling ______ resistance will increase as it falls ______________ ______ resistance will increase as it falls ______________ An ________________ force on the object An ________________ force on the object Eventually __________ will ______________ with _______ resistance Eventually __________ will ______________ with _______ resistance Reaches _____________ velocity - highest speed reached by a falling object. Reaches _____________ velocity - highest speed reached by a falling object.

Terminal velocity Force of gravity is constant Force of gravity is constant u air resistance ___________ as you speed up u until the force is _________ u _____________ forces, no ________________________ u ______________ velocity _______________ velocity

_______________ Velocity and _____________ Acceleration

__________________ Velocity and ______________ Acceleration

_________________ Velocity and ______________ Acceleration

____________________ Velocity and _______________ Acceleration