andre, whose mass is 77.1 kg, sits on a divin...

andre, whose mass is 77.1 kg, sits on a diving board above a dunk tank. if he is sitting 0.90 m above the water, what is his total mechanical energy? j

Answer

# Explanation: ## Step1: Identify the formula The total mechanical energy $E$ of an object at rest above the ground is its gravitational - potential energy $U = mgh$, where $m$ is the mass, $g$ is the acceleration due to gravity ($g = 9.8\ m/s^{2}$), and $h$ is the height. ## Step2: Substitute the values Given $m = 77.1\ kg$, $g=9.8\ m/s^{2}$, and $h = 0.90\ m$. Then $U=mgh=77.1\times9.8\times0.90$. ## Step3: Calculate the result $77.1\times9.8\times0.90=(77.1\times9.8)\times0.90 = 755.58\times0.90=680.022\ J$. # Answer: $680.022$