Biomechanics – Numerical Final Exam Review

Flashcards to review key concepts and calculations from the Biomechanics Numerical Final Exam.

What is the kinetic energy of a lower leg with a moment of inertia of 2 kg·m² rotating at 2.1 rad/s?

Kinetic Energy = 4.41 J

How much mechanical energy is generated when a 70 kg patient extends the knee causing a height rise of 0.31 m?

Mechanical Energy = 17.63 J

What is the maximum safe walking angle if the horizontal heel force must not exceed 0.15W when walking at a 50° step angle?

Maximum angle = 34°

What is the minimum coefficient of friction required to prevent slipping when walking at a step angle of 50°?

Minimum µ = 0.467

What work is done by the heart per unit volume if blood exits the ventricle at 16 kPa with a height rise of 0.15 m?

Work per unit volume = 17,550 J/m³

Calculate the work done by the heart in one beat using a stroke volume of 60 cm³.

Work per beat = 1.06 J

If the heart beats at 70 beats per minute, what is the average power output?

Average power = 1.23 W

What is the mean blood velocity when the aortic flow rate is 5 L/min under laminar flow conditions?

Mean velocity = 0.27 m/s

Using Reynolds number criteria, what is the critical velocity at which eddy flow begins in the aorta?

Critical velocity = 0.4 m/s

Calculate the volumetric flow rate of an arteriole with a radius of 35 µm and a pressure difference of 10 mmHg with blood viscosity of 3.5 cP.

Flow rate = 0.135 mL/min