Question

An athlete is performing squats in the weight room. The knee is going from anatomical position to 92 degrees and then back to anatomical position each squat. The athlete performs a total of 10 squats. This is done over a time period of 30 seconds. What is the angular acceleration (rad/sec 2) of the knee

Answer 1

α = 0.357 ras / s²

Step-by-step explanation:

This is a rotational kinematics exercise, it tells us that it performs 10 squats in 30 s, for which it performs one squat at t = 3 s, also indicates that the angle of the squat is θ = 92º

θ = θ₀ + w₀ t + ½ α t²

the athlete starts from rest, whereby w₀ = 0 and the initial angle in the vertical position is zero (θ₀=0)

θ = ½ α t²

α = 2 θ /t²

let's reduce the magnitudes to the SI system

θ = 92º (π rad /180º) = 0.511π rad

let's calculate

α = 2 0.5111π /3²

α = 0.1136π rad / s²

α = 0.357 ras / s²