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Getting faster? (accelerating). distance. time. Getting faster (accelerating). distance. time. Examples. distance. time. A car accelerating from stop and then hitting a wall. distance. time. Speed against time graphs. speed. time. Speed against time graphs. speed. time.
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Getting faster? (accelerating) distance time
Getting faster (accelerating) distance time
Examples distance time
A car accelerating from stop and then hitting a wall distance time
Speed against time graphs speed time
Speed against time graphs speed time
No movement? speed time
No movement speed time
Constant speed? speed time
Constant speed speed time
Constant speed How would the graph look different for a faster constant speed? speed time
Constant speed speed fast time
Constant speed How would the graph look different for a slower constant speed? speed fast time
Constant speed speed fast slow time
Getting faster? (accelerating) speed time
Getting faster? (accelerating) speed Constant acceleration time
Getting faster? (accelerating) speed The gradient of this graph gives the acceleration time
Getting faster? (accelerating) v The gradient of this graph gives the acceleration speed a = v – u t (v= final speed, u = initial speed) u time
Getting faster? (accelerating) speed The area under the graph gives the distance travelled time
Example: speed time
A dog falling from a tall building (no air resistance) speed time
A dog falling from a tall building (no air resistance) speed time
A dog falling from a tall building (no air resistance) speed Area = height of building time
distance speed time time Be careful!
distance speed time time No movement
distance speed time time Constant speed gradient = speed Area under graph = distance travelled
distance speed time time Constant acceleration Gradient = acceleration = a = (v-u)/t Area under graph = distance travelled
Distance time graphs ;Summary • The gradient of a distance time graph gives the velocity • increasing gradient means object is accelerating • decreasing gradient means object is decelerating • zero gradient means object is stationary
Velocity time graphs; Summary • The gradient of a velocity time graph gives the acceleration of an object • the area under a velocity time graph gives the total distance traveled • Increasing or decreasing gradient gives the rate at which the acceleration is increasing or decreasing • Zero gradient means the object is travelling at constant speed
Problems 5, 0, 3.75m 1. Calculate the speed over OA AB and BC 2. Calculate (a)the acceleration over OA, AB and BC (b) the total distance traveled in the 12 s 5m/s2, 0, 3.75m/s2, 127.5m