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Maths a level questions

image.jpgFor the graph, how do you get average velocity and average speed for the dog? I got it wrong as it did speed= 150/100 and velocity=-100/100 but the answers should be speed=4 4/9 ms^1 and velocity= -1 1/9 but how?
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Original post by Lucofthewoods
image.jpgFor the graph, how do you get average velocity and average speed for the dog? I got it wrong as it did speed= 150/100 and velocity=-100/100 but the answers should be speed=4 4/9 ms^1 and velocity= -1 1/9 but how?


Average speed is the total distance travelled divided by the time taken.
Average velocity is the displacement divided by the time taken. Make sure you know how to calculate distance and displacement from the graph - they are not the same.
Original post by Lucofthewoods
image.jpgFor the graph, how do you get average velocity and average speed for the dog? I got it wrong as it did speed= 150/100 and velocity=-100/100 but the answers should be speed=4 4/9 ms^1 and velocity= -1 1/9 but how?


Average speed is total modulus(distance) travelled/total time

Average velocity is total distance travelled/total time.
Original post by Lucofthewoods
image.jpgFor the graph, how do you get average velocity and average speed for the dog? I got it wrong as it did speed= 150/100 and velocity=-100/100 but the answers should be speed=4 4/9 ms^1 and velocity= -1 1/9 but how?


The total time is 90 not 100 (look at the scale more carefully).

The total distance travelled is 150 one way, 150 back to the start and then 100 the other way.

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