Torque and power outputs on skilled and unskilled users during manual wheelchair propulsion

Seonhong Hwang1, Seunghyeon Kim, Youngho Kim

  • 1Department of Biomedical Engineering, Yonsei University, Wonju, Gangwon, South Korea. shhwang@yonsei.ac.kr

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Torque

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Net Torque Calculations

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Work and Power for Rotational Motion01:27

Work and Power for Rotational Motion

Work and power in rotational motion are completely analogous to work and power in translational motion. The total work done to rotate a rigid body through an angle 'θ' about a fixed axis is the sum of the torques integrated over the angular displacement. Hence, torque and angular displacement in rotational motion are analogous to force and linear displacement in translational motion, respectively.
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Rolling Resistance: Problem Solving01:17

Rolling Resistance: Problem Solving

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Torque Free Motion

The torque-free motion refers to the movement of a rigid body in space when no external torques are acting upon it. This type of motion can be observed in environments where there are no external forces or frictions, like in outer space. For example, a rotation of Mars in space is a torque-free motion. Mars is an axisymmetric object, meaning it has an axis of symmetry along which it rotates, designated as the z-axis. The rotating frame of reference is defined such that the center of mass of...
Power Expended by a Constant Force00:57

Power Expended by a Constant Force

The relationship between work done and the time taken to do it can be explained using the concept of power. For example, several sprinters in a race may have the same velocity when they reach the finish line, therefore doing the same amount of work, but the winner does it in the least amount of time. Thus, power is defined as the rate of doing work. Since work can vary as a function of time, the average power is defined as the work done during a time interval, divided by the time interval.