Question

margy is trying to improve her cardio endurance by performing an exercise in which she alternates walking and running 100.0 m each. if margy is walking at 1.4 m/s and accelerates at 0.20 m/s² during one of the running portions, what is her final velocity at the end of the 100.0 m? round your answer to the nearest tenth. m/s

Explanation:

Step1: Identify the kinematic - equation

We use the equation $v^{2}=v_{0}^{2}+2ax$. Here, $v_{0}$ is the initial velocity, $a$ is the acceleration, $x$ is the displacement, and $v$ is the final velocity.

Step2: Substitute the given values

Given $v_{0}=1.4\ m/s$, $a = 0.20\ m/s^{2}$, and $x = 100.0\ m$. Substitute into the equation: $v^{2}=(1.4)^{2}+2\times0.20\times100.0$.
First, calculate $(1.4)^{2}=1.96$ and $2\times0.20\times100.0 = 40$. Then $v^{2}=1.96 + 40=41.96$.

Step3: Solve for $v$

Take the square - root of both sides: $v=\sqrt{41.96}\approx6.5\ m/s$.

Answer:

$6.5$