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The period of the leg can be approximated by treating the leg as a physical pendulum, with a period of , where I is the moment of inertia, m is the mass, and h is the distance from the pivot point to the center of mass. The leg can be considered to be a right cylinder of constant density. For a man, the leg constitutes 16% of his total mass and 48% of his total height.Find the period of the leg of a man who is 1.85 m in height with a mass of 65 kg. The moment of inertia of a cylinder rotating about a perpendicular axis at one end is (m*l^2)/3___________ sec

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This question is incomplete, the complete question is;

The period of the leg can be approximated by treating the leg as a physical pendulum, with a period of 2π√[
I / mgh ] , where I is the moment of inertia, m is the mass, and h is the distance from the pivot point to the center of mass. The leg can be considered to be a right cylinder of constant density. For a man, the leg constitutes 16% of his total mass and 48% of his total height. Find the period of the leg of a man who is 1.85 m in height with a mass of 65 kg. The moment of inertia of a cylinder rotating about a perpendicular axis at one end is (m*
l^2)/3___________ sec.

Answer:

the period of the leg of the man is 1.5 sec

Step-by-step explanation:

Given the data in the question;

Time period = 2π√[
I / mgh ]

also, The moment of inertia of a cylinder rotating about a perpendicular axis at one end is ( m
l^2/3)


I = m
l^2/3 and h =
l/2

hence;

Time period = 2π√[ m
l^2/3 / mgh ]

Time period = 2π√[ m
l^2 / 3mgh ]

Time period = 2π√[
l^2 / 3g(
l/2) ]

Time period = 2π√[ 2
l^2 / 3g
l ]

Time period = 2π√[ 2
l / 3g ]

now,
l = 48% of 1.85 = 0.48 × 1.85 = 0.888 m

acceleration due to gravity g = 9.8 m/s²

so we substitute these values into the equation;

Time period = 2π√[ (2×0.888 ) / (3×9.8) ]

Time period = 2π√[ 1.776 / 29.8 ]

Time period = 2π√[ 0.059597 ]

Time period = 2π × 0.24412

Time period = 1.5 sec

Therefore, the period of the leg of the man is 1.5 sec

User Barrowc
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