Velocity and Acceleration Test Study Guide



MOTION: Velocity and Acceleration Test Study Guide

You will need to know:

• The difference between distance and displacement

• How to draw or read a motion map (the dots) . . . . . .

• That velocity and speed are basically the same, but velocity has a direction

• How to read a distance / time graph

• How to read a velocity / time graph

• How to calculate the average velocity of a given timeframe

• How to use the formula for velocity to calculate velocity, distance or time

v = d

t

• How to calculate the acceleration of an object, or be able to use the formula for acceleration to find the unknown variable

a = vf-vi

t

Below is a position (distance)/time graph

Average velocity is the total distance divided by the total time (in a given time frame)

For example: If I gave you a graph like the one below and asked you to calculate the average velocity of Charlie’s run, you would take the total distance run and divide by the total time. V= 100m / 17 seconds = 5.88m/s

BUT if I asked you to calculate the average velocity for the first part of his run from start to 8 seconds, you would calculate v= 50m/8s = 6.25 m/s

[pic]

When looking at a velocity / time graph, you can tell if something is going a constant velocity or accelerating based on the shape of the line.

Look at the graph below to answer the following questions:

1. Which segments show a constant velocity? _____________

2. Which segments show a positive acceleration (speeding up)? ____________

3. Which segments show a negative acceleration (slowing down)? ____________

[pic]

In the graph above, if I asked: Calculate the acceleration for segment D-E, you would take the final velocity at E (5m/s) and subtract the velocity at D (0m/s), then divide by the time of that segment which is 5s.

5 - 0

a= 5

a= 1m/s2

Things to remember…

• The slope of the line (how steep it is) will tell us if something is going faster or slower. The steeper the slope, the faster the object

• Velocity is a rate, so you will always have some unit per time unit : m/s, km/hr, etc.

• Acceleration is a rate of velocity, so the time unit will usually be squared: km/hr2 m/s2 etc.

If you have access to the internet, remember that I have the powerpoints and some of our worksheets we practiced with.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download