The moment of inertia of the human body about an axis through
its center of mass is important in the application of biomechanics
to sports such as diving and gymnastics. We can measure the body's
moment of inertia in a particular position while a person remains
in that position on a horizontal turntable, with the bodys center
of mass on the turntable's rotational axis. The turntable with the
person on it is then accelerated from rest by a torque that is
produced by using a rope wound around a pulley on the shaft of the
turntable. From the measured tension in the rope and the angular
acceleration, we can calculate the body's moment of inertia about
an axis through its center of mass.
(Figure 1)
Part A
The moment of inertia of the empty turntable is 1.5 kg?m2. With a constant torque of 2.5 N?m, the turntableperson system takes 3.0 s to spin from rest to an angular speed of 1.0 rad/s. What is the persons moment of inertia about an axis through her center of mass? Ignore friction in the turntable axle.
The moment of inertia of the empty turntable is 1.5 . With a constant torque of 2.5 , the turntableperson system takes 3.0 to spin from rest to an angular speed of 1.0 . What is the persons moment of inertia about an axis through her center of mass? Ignore friction in the turntable axle.
2.5 kg?m2 | |
6.0 kg?m2 | |
7.5 kg?m2 | |
9.0 kg?m2 |
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