OBJECTIVES OF THIS SITE

• Students will be able to recognize the four kinematic equations
• Students will apply the kinematic equations to solve for velocity, time, acceleration, and distance of moving objects.
• Students will be able to identify real-life applications of the kinematic equations.
• Students will understand the units and variables involved in the use of the kinematics.

CONCEPTS

A. The Equations
  1. V= Vo + at
     2. X= 1/2 (V + Vo) t
     3. X= Vo t + 1/2 at^2
     4. V^2= Vo^2 + 2ax

B. Acceleration
  1. Gravity is measured as 9.8 m/s^2. If an object is being thrown upward, its acceleration is -9.8m/s^2. If it is falling than its acceleration is 9.8m/s^2.
     2. Acceleration is measured in meters per second squared. (m/s^2)
     3. Acceleration is how fast something is speeding up or slowing down.

C. Velocity
  1. Initial Velocity is called V-Not. (Vo)
      2. Final Velocity is V.
      3. Velocity is measured in meters per second (m/s).
      4. Velocity is how fast something moves.

D. Time
      1. Time is how long it takes for an object to move from one position to another.
      2. Time is measured in seconds. (s)
      3. An object's time will always be positive.

E. Distance
  1. Distance is how far an object travels in a certain amount of time.
      2. Distance is measured in meters. (m)
      3. An object's distance will always be positive.

    The Kinematic Equations have a lot of uses in your everyday life. Here is a list of some of those applications.

• Projectile Motion- The kinematics can help you to find out what is the best way to launch something. The army and navy need to figure out things like this all the time.
• Cars- Car manufacturers can use the kinematics to figure out stopping distance, top speed, and various other things based on certain variables.
• Drag Racing- Yes, science can help you beat someone in a drag race. Say you're up against a BMW Z3. You're going to need to go pretty fast to beat it. If you know how fast he can accelerate to his top speed, you can figure out how fast you will need to go in order to beat him.
• Airplanes- Let's say that an airplane needs to get to a certain speed in order to take off before the runway runs out. Using the kinematics, you can figure out how fast the pilot will need to accelerate.

Formulas                       Variables
V= Vo + at                     Vo=initial velocity
x= 1/2 (V + Vo) t           V= final velocity
x= Vo t + 1/2at^2          a=acceleration
V^2=Vo^2 + 2ax           t= time
                                      x=distance

Units
>Initial velocity and final velocity are both measured in meters per second (m/s)
>Acceleration is measured in meters per seconds squared (m/s^2)
>Time is measured in seconds. (s)
>Distance is measured in meters (m)

Sample Problem 1
A car accelerates from 25 m/s to 40 m/s in 9 seconds. Solve for the acceleration.

SOLUTION

Sample Problem 2
Vin Diesel's car in The Fast and the Furious uses nitrous oxide tanks to boost his acceleration. Vin starts out from rest. If the nitrous allows him to accelerate at 20 m/s, how long would it take him to reach his final speed of 95 m/s?

SOLUTION

Sample Problem 3
A tractor trailer travels 300 meters in 35 seconds, starting from rest. Solve for the final velocity.

SOLUTION

Click here to go back to the Ohm's Law page.
Click here to see a page on the first 2 kinematics.
Click here to see a page on the last 2 kinematics.
Click here to go to the main physics page.