Aflea jumps straight up to a maximum height of 0.470 m . what is its initial velocity v0 as it leaves the ground?

We use kinematic equation,

Here, is final velocity and a is acceleration and s is maximum height.

Given,   and we take a as negative value of acceleration due to gravity .

At the maximum height, final velocity is zero.

Substituting these values in above equation, we get

Therefore, the initial velocity with it leave the ground is 3.03 m/s.

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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