Physics Basic Motion

VOCABULARY SYMBOL FORMULA DESCRIPTION position (m)   x  How far an object is from the reference.  displacement  ∆x  How far an object has moved from where it started.  delta ∆ ∆x = x –xo  Delta represents change. Final minus initial.  distance d  The full length of the path an object followed.  time (s) t  velocity (m/s) v  v = ∆x ∆t  Displacement divided by time.  speed s  s = d Distance divided by time. acceleration (m/s2) a   a = ∆v  How quickly velocity changes. Make sure you have the information in the table copied in your notes correctly. Be sure to fill in boxes that were not filled in from the reading.

Velocity and Train Tracks NEVER start with your speed station. Speed station can be written upside down or either direction. Start with what we know.

Samantha can run 5 miles in 35 minutes Samantha can run 5 miles in 35 minutes. How far could she run in one week? Speed Station 5 mi 35 min 1 wk 7 days 24 hr 60 min 5 mi = 1440 mi 1 wk 1 day 1 hr 35 min

A lion can run 50 mph (miles per hour) A lion can run 50 mph (miles per hour). How many minutes would it take a lion to run from SLC to Los Angeles? (A distance of 1300 kilometers.) Speed Station

Spider Analogy d ∆x

.25 hr PROVO AF SLC 30 miles .5 hr 40 miles 1.5 hr Bob starts in American Fork. Then he jumps in his car and drives 30 miles to Salt Lake City. It takes him half an hour to get there. Then he turns around and drives south to Provo (which is 40 miles away from SLC). It takes him an hour and a half to get there because of traffic. Then he drives home to American Fork. It only takes a quarter of an hour to get home. PROVO AF SLC .25 hr 30 miles .5 hr 40 miles 1.5 hr

Let’s look at each piece of the journey because each individual piece is STRAIGHT speed and velocity will be the same. AF  SLC v = ∆x ∆t = 30 mi .5 hr = 60 mph s = d t = 30 mi .5 hr = 60 mph

Let’s look at each piece of the journey because each individual piece is STRAIGHT speed and velocity will be the same. SLC  PROVO v = ∆x ∆t = - 40 mi 1.5 hr = - 26.7 mph s = d t = 40 mi 1.5 hr = 26.7 mph

Let’s look at each piece of the journey because each individual piece is STRAIGHT speed and velocity will be the same. PROVO  AF v = ∆x ∆t = 10 mi .25 hr = 40 mph s = d t = 10 mi .25 hr = 40 mph

Now let’s look at big chunks of the journey Now let’s look at big chunks of the journey. This is where speed and velocity will diverge. AF  PROVO speed = distance time = 70 mi 2 hr = 35 mph velocity = displacement time = -10 mi 2 hr = -5 mph

OVERALL TRIP speed = distance time = 80 mi 2.25 hr = 35.6 mph velocity = displacement time = 0 mi 2.25 hr = 0 mph