Answer:
0.3 seconds
Step-by-step explanation:
When we walk, our legs alternatively swing forward about the hip joint as a pivot. In this motion the leg is acting approximately as a physical pendulum. Treating the leg as a thin uniform rod of length 0.80 m,
To find the time it takes for the leg to swing forward, where g = 9.8 m/s^2
Let's use the simple pendulum formula which says that:
T = 2π( sqrt ( L/g))
T = 2π[sqrt (0.8/9.8)]
T = 2π × 0.082
T = 0.5129
For the leg to swing forward only, the number of complete oscillations will be half.
Period T = time t ÷ number of complete oscillations. That is,
T = t ÷ 1/2
0.5129 = t ÷ 1/2
t = 0.5129 × 1/2
Time t = 0.256 seconds.
Therefore, the time it takes for the leg to swing forward is 0.3 seconds approximately