slide1
Download
Skip this Video
Download Presentation
Acceleration

Loading in 2 Seconds...

play fullscreen
1 / 15

Acceleration - PowerPoint PPT Presentation


  • 302 Views
  • Uploaded on

Acceleration. Change in Velocity. Each time you take a step you are changing the velocity of your body. You are probably most familiar with the velocity changes of a moving bus or car. The rate at which velocity (speed or direction) changes occur is called acceleration.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Acceleration' - jaden


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
change in velocity
Change in Velocity
  • Each time you take a step you are changing the velocity of your body.
  • You are probably most familiar with the velocity changes of a moving bus or car.
  • The rate at which velocity (speed or direction) changes occur is called acceleration.
slide3
Acceleration= final velocity- starting velocity

time

Change in velocity = final – starting velocity velocity

Acceleration= change in velocity

time

slide4

A car traveling at 60 mph accelerates to

90 mph in 3 seconds. What is the

car’s acceleration?

Velocity(final) - Velocity(original)

=

Acceleration

time

90 mph - 60 mph

=

3 seconds

30 mph

=

3 seconds

=

10 mph/second

slide5

Positive acceleration

Negative acceleration

slide6

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?

Velocity(final) - Velocity(original)

=

Acceleration

time

0 mph - 60 mph

=

6 seconds

- 60 mph

=

6 seconds

=

- 10 miles per hour per second

slide7
- A constant acceleration produces a straight line or linear slope (rise/run). - The slope of a non-linear velocity-time graph (rise/run) will predict an objects instantaneous acceleration. a = v/t
free fall
Free fall
  • The constant acceleration of an object moving only under the force of gravity is "g".
  • The acceleration caused by gravity is 10 m/s2
  • If there was no air, all objects would fall at the same speed
  • Doesn’t depend on mass
  • After 1 second falling at 10 m/s
  • After 2 seconds 20 m/s
  • 3 seconds 30 m/s
galileo
Galileo
  • 1600’s
  • Studied how things fell
  • Didn’t have a good clock
  • Rolled balls down an inclined plane
  • Found that the speed increased as it rolled down the ramp
galileo1

t = 0

t = 1 second

t = 2 seconds

t = 3 seconds

Galileo

Acceleration= change in velocity

time

galileo2
Galileo
  • Same things happen when things fall
  • Didn’t drop things from Tower of Pisa
v 2 final 2gd y
v2final = 2gdy
  • A final velocity can be calculated over a vertical displacement “dy" during free fall using the equation:
d y 1 2 gt 2
dy = 1/2 gt2
  • The vertical displacement “dy" that occurs during a specific time of free fall can be determined using the equation:
  • Or a time interval can also be determined over a specified distance of freefall using the equation:

t2 = 2dy /g

falling
Falling
  • Air resistance will increase as it falls faster
  • An upward force on the object
  • Eventually gravity will balance with air resistance
  • Reaches terminal velocity - highest speed reached by a falling object.
terminal velocity
Terminal velocity
  • Force of gravity is constant
  • air resistance increases as you speed up
  • until the force is equal
  • Equal forces, no acceleration
  • constant velocity terminal velocity
ad