1. Solving Word Problems Using Kinematics Equations

2. Example Problem
A fan cart takes 5.16 seconds to travel 2.0m from a standing start. How long will it take this same car to travel 4.0m, again from a standing start?

3. Equations Duration Dt = tf – ti Displacement Dx = xf –xi
Avg Speed Savg = d / Dt
Avg Velocity vavg = Dx/Dt
Avg Acceleration aavg = Dv/Dt

4. Kinematics Equations For Constant Acceleration
Dx = vit + ½ at2
vf = vi + at
Dx = ½(vi + vf)t
Vf2 = vi2 + 2aDx

5. Terms – Definitions
-time - -duration - -position - -distance - -displacement - -speed - -velocity - -acceleration - Which of these terms relates two other terms?

6. Ex. From a stand-still, a train can cover 100m in 20 seconds.
What is the train’s acceleration? (assume it is constant)
With the same constant acceleration, how long would it take the train to complete 400m (a quarter mile) from a standing start?

7. Ex
In the automotive industry, a 0.5g panic stop is the name for a situation when a driver slows the vehicle by ½ the acceleration due to gravity. That means the car is slowed by 4.9m/s/s. How far will it take a driver to execute a 0.5g panic stop from:
25 mph?
50 mph?