Adummy is fired vertically upward from a canon with a speed of 40 m/s. how long is the dummy in the air? what is the dummies maximum height?

8,1549 seconds

81,5494 meters is the maximum height

Explanation:

REmemeber that in physiscs the formula for maximum height is given by the next representation:

Sow we just have to insert the values into the formula:

Now the time that it takes the dumy to fall from that height is given by thenext formula, and then we just multiply that by 2 to calculate the time that the dummy was in the air:

Now we insert the data we have into the formula:

in free fall the amount of time it takes an object going up is the same amount of time it take to fall, so we just multiply the time falling by 2 and we get taht the dummy was in the air for 8.1549 seconds.

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