Significant Figures
How many sig figs is in this number?
4.728
4 sig figs
True or False chemistry is a physical science?
True! And so is physics, geology, meteorology, and astronomy
What is the standard unit for length?
Meter
It has magnitude and direction
How many sig figs in this number?
00.02790
4 sig figs
What is the scientific method?
General methods of observations rules for reasoning, and making predictions
How many mm in a meter?
1000mm in 1 meter
What is the difference between speed and velocity?
Speed only has magnitude (scalar quantity)
Velocity has magnitude and direction (vector)
How many sig figs should be in the answer?
1 sig fig
What can the scientific method be broken into
Observations & measurements
hypothesis
experiments
theory
law
What does mega (M) mean?
1,000,000 times the base
How far would a car travel that is going 20m/s in 10 seconds?
V=d/t so vt=d
(20m/s)(10s)=200m
In the following operation 4532.937/29526.902
How many sig figs should be in the answer?
7 sig figs
Whats the difference between theory and law?
Theory explains the behavior and law states the finding
Convert 70mph to ft/sec
1 mi=5280ft
102.667 ft/sec
A race car starting from rest accelerates uniformly along a straight track, reaching a speed of 90km/h in 7.0s. Find its acceleration.
What is given and wanted in this problem?
V0=0 vf=90km/h t=7.0s
wanted: acceleration in m/s^2
When do you do the rounding for sig figs?
At the end of the operation
What is this an example of?
If I drop two balls with two different masses at the same time, then the ball with the larger mass will hit the ground first.
Hypothesis
Convert 10 yd to m
1yd=0.914m
9.14m
A ball is dropped from a tall building how far does the ball drop in 1.50s?
D=1/2gt2=1/2(9.80m/s2)(1.5s)2
D=11M