• Distance vs. DisplacementDistance the total path traveled. no direction (scalar)

Displacement from the very beginning to the very end.

includes direction so it is a vector

AE

DC

B

d = A + B + C + D + E

x = resultant

symbol for distance

symbol for displacement(sometimes y)

R

• Speed vs. VelocitySpeed (v) distance divided by time (no direction, scalar)

Velocity (v) displacement divided by time (vector)

xv

t

measured in

second

meters m

s

equation

Heather and Matt walk with an average velocity of 0.98 m/s eastward. If it takes them 34 min to walk to the store, what is their displacement?

Givens:

t = 34 minv = 0.98 m/s

Step 2: Write out givens.

Step 5: Substitute.

Step 4: Write out equation.

Step 3: Convert units if necessary

Step 6: Solve.

602040

1min

sx s

x = v t

x = (0.98)(2040)

x = 2000 m

Step 1: Draw a picture.

• Some key points:

• Remember: Velocity includes magnitude and direction

• In one dimension, speed and velocity are calculated the same way.

• Acceleration change in velocity How fast you change how fast you’re going

can change two ways: either change the magnitude or the direction.

5 total variables

x – displacementvi – initial velocityvf – final velocitya – accelerationt – time

Acceleration can be found as follows:

a = vf– vi / t

This equation says that Acceleration = final velocity – initial velocity divided by time

http://www.physicsclassroom.com/mmedia/kinema/avd.cfm

symbol is “a”

unit is m/s2

A sailboat starts from 0 m/s (rest) and accelerates at a rate of 0.21 m/s2 for 3 seconds. a. find the magnitude of

the boat’s final velocity

• More key points:• Acceleration and velocity are NOT,

NEVER HAVE BEEN, and NEVER WILL BE, the same thing.

• http://www.physicsclassroom.com/mmedia/kinema/acceln.cfm

• Acceleration is the rate of CHANGE in velocity.

• So, velocity is a rate; a change in distance over time.

• Acceleration is a rate; a change in velocity • over time. Speeding up, slowing down, turning