Quiz Review

The good students will take copious notes.

The Topics You Need To Study

• Unit Conversions• One dimensional Motion– Solving for distance– Solving for time– Solving for velocity– Solving for acceleration

• Vectors– Finding magnitude

Unit Conversions

• DO NOT WRITE MPH!!! Instead, write miles/hr (this will help you keep from getting confused)

• 1600 meters = 1 Mile• 1.6 km = 1 Mile• 3600 Seconds = 1 hr

Unit Conversions cont’d

• Remember, when converting units, each section of the picket fence (after the first) must be an equivalency (i.e. 1 mile/1600 m, or 1 hr/3600 sec)

• Put the unit you want to cancel OPPOSITE (numerator or denominator) – Example:

25 miles

1 hr1 hr

3600 sec 1 mile

1600 meters

Distance, Time and Velocity

V T

D

USE THETRIANGLE!

How do we find D?How do we find V?How do we find T?

Remember: D = VXT is basically one equation!!

Velocity, Acceleration and Time

A T

V

USE THETRIANGLE!

How do we find V?How do we find A?How do we find T?

Remember: V = A X T is basically one equation!!

Strategies

• Identify what the question is asking for – look for phrases like– How long…? (answer should be a time in sec or

min or hours)– How far…? (answer should be distance in meters

or km or miles)– How fast…? (answer should be speed/velocity in

m/s or km/h or miles/hr)– What is the acceleration of…? (answer should be

an acceleration in m/s2)

Write down known info

• Distance = ?• Time = ?• Acceleration = ?• Velocity = ?• “Starts from rest…” → Vi = 0

Identify the completely missing quantity

• This will help you identify which of the four basic equations you need.• V = D/T• A = V/T

Vector Stuff

• Remember: find the magnitude (length) of a vector by Pythagorean Theorem

• Pythagorean Theorem : A2 + B2 = C2

Dr. Mason’s Helpful Hints

• Remember your units• Understand the difference between velocity

and acceleration• Likewise, understand the difference between

m/s and m/s2

• Remember: Δanything = final - initial• Beware of writing units we have NEVER used

in class. Examples: miles/hour2, m/s3

• Remember what negative acceleration means

Lest we forget…

•There is gravity on the moon. Accept it and move on.