Units
What is a symbol for 'kilogram'?
kg
In D = tv, v is a symbol for this variable.
What is velocity?
In F = ma, what are F, m, and a called?
variables
What is the name of 'v' in D = tv
VELOCITY?
A squirrel jumped from tree to tree with the velocity of 6m/s in 3s. How far apart are the two trees from each other?
What is the NAME of one of the KNOWN VARIABLES?
VELOCITY or TIME
What is the name of this unit symbol, m/s?
meters per second
In Distance = time x velocity problems,
'how long does it take...?' means the problem is asking for this variable.
What is TIME?
What is a group of variables organized into a mathematical relationship, like F=ma, called?
FORMULA
What is a symbol for meters?
m
A 2kg soccer ball fell to the ground at the acceleration rate of 9.8 m/s2. This is the TWO KNOWN UNIT SYMBOLS.
kg and m/s2
The unit we use to measure Force is named after this scientist.
Isaac Newton
In D = tv, when the problem is asking 'How far..?' it is asking for this variable.
What is DISTANCE?
In V = 12km / 3m/s,
what are 12 and 3?
VALUES
What is the name for the symbol [ m/s2 ]?
METERS PER SECOND SQUARE?
A book is pushed with the force of 30 N. It accelerates at 10 m/s2. What is its mass?
What is the UNIT of the UNKNOWN variable?
KILOGRAM
What is a quick way to find out if something is a unit.
Units come after the number?
When the problem is "asking how fast...?", it is asking for this variable.
VELOCITY
In W=mg, gravitational acceleration (g) is most similar to which variable in F=ma?
ACCELERATION (a).
Convert the units: kg = N / m/s2 into a formula with variables.
m = F / a?
What is the difference between W=mg and
W = 10kg x 9.8m/s2?
W = mg is a FORMULA and
W = 10kg x 9.8m/s2 is an EQUATION
What are units for?
measurement
What makes a variable different from a unit?
A variable varies or changes and a unit does not change.
If Force in F=ma describes objects moving in all directions, Weight is a special kind of Force that describes objects moving towards this area. See the picture on the board.
Center of a planet
And what unit has a symbol m?
MASS and METER
Use V = D/t to find the velocity of a caterpiller that covered 10 centimeters in 5 seconds.
What is the equation for this problem?
V = 10cm/5sec