Motion ISCI 2002

Speed: change in distance over time Speed =  d /  t Constant vs. Average Speed Speed is a ‘scalar’ quantity No directional properties Speed

Velocity: includes the speed of an object plus direction. Velocity =  d /  t + direction! Displacement Object moves from one location to another Distance and direction from a starting point Velocity

Displacement

Vectors: have both magnitude and a direction Velocity, acceleration, displacement, etc. Vectors are represented by arrows Velocity and Displacement are Vectors

Parallel vectors can be summed When vectors are at right angles (a) can be summed (b) use trigonometry rules to solve Pythagorean Theorem How is the direction calculated? Vector Summation

Vector Addition

The so-called parallelogram law gives the rule for vector addition of two or more vectors. For two vectors and, the vector sum is obtained by placing them head to tail and drawing the vector from the free tail to the free head.parallelogram lawvector sum

Vector Resultant

Acceleration: is a change in the velocity of an object. Acceleration =  v /  t When you change directions, slow down, speed up, turn you are undergoing acceleration. Acceleration may be (+) or (-) Acceleration

Speed or velocity at any given moment in time Speedometer in your car Instantaneous Speed and Velocity When speed is not constant draw a tangent across the point in time

Graphs Straight-line or linear slope indicates a direct or proportional relationship between the variables Speed or velocity at that specific time If not proportional Slope of the line tangent to the curve of the line Motion and Graphs

Slope: rise/run Change in position (y) over time (x) Graphical Slopes

Calculating the Slope of a Graph

Distance-Time Graphs Constant velocity (+10 m/s); No acceleration Changing, positive velocity – acceleration (change in velocity)

Constant Velocity – No Acceleration

Velocity – Time Graphs Zero Acceleration

Constant Velocity – Zero Acceleration

Velocity-Time Graphs (Acceleration)