HELP !!! For Motion Questions

This sheet is your lifeline to the motion (acceleration and speed) questions we are working with right now. When in doubt, check this sheet, hopefully it will give you the answers you are looking for.

Q. Help! The question doesn’t make sense!

           A. If you cannot figure out what numbers represent which value (i.e. they give you a number, but is it a speed value? a distance? a time? an acceleration value?) then look at what comes after the number. The units will always tell you what type of value it is.

           It is a distance if the unit that follows the number is:

·   Meters (m)

·   Centimeters (cm)

·   Kilometers (Km)

·   Millimeters (mm)

It is a time if the unit that follows the number is:

·   Seconds (s)

·   Minutes (min)

·   Hours (h)

·   Days (d)

It is a speed if the unit that follows the number is a distance measurement / time measurement (for example km/h or km/s or m/s)

It is acceleration if the unit that follows the number is a distance measurement / time measurement squared (for example km/h or km/s or m/s). Keep in mind that the units for acceleration can also be written as a distance measurement / time measurement / time measurement (For example km/h/s or m/h/s).

Q. Help! I don’t know which formula to use!

A. If you don’t know which formula to use, try making a list of all of the information they give in the question. Then add the unknown (what you are looking for) to your list. This should give you a list of what your formula needs to contain. Then search the formulas we have used so far for the right one.

We have seen 3 different formulas so far in this class, one for speed and 2 different ones for acceleration.