Where and When?! Ch. 3 Section 2
Coordinate Systems Tells you where the zero point of the variable is located and the direction in which the values measured increase Origin Point at which the variables have a value of zero 100 meter dash runner?
Measure in two dimensions Need to know direction parallel to the ground and the height above the ground Two axes X axis Horizontal direction (Parallel Y axis Vertical direction (Perpendicular) Location of position of a given time is determined by a Position Vector Length is proportional to the distance from the origin
Negative Position Where would a subject be in a coordinate system if its position is negative? Left of the origin
Vectors and Scalars Scalar Quantity Recorded measurement that only tells you the magnitude Temperature (T), Time (t), Mass (m) Vector Quantity Recorded measurements that has both magnitude and direction Represented by a letter with arrow over it Velocity (v) What is the vector distance from Baltic to Brookings ? About 40 miles North
Time Intervals and Displacement Motion of a sprinter Need a Scalar quantity and vector quantity Time is __________ Time interval is needed ( Δt) t 0 is the starting time = 0 t 1 time at finish line = 11.5 sec Δ t = t 1 – t 0 Displacement is the distance between 2 points meters Δ d = d 1 – d 0
Find Distance and displacement Total distance = 95 yds Total displacement = 55 yds to the left