Biomechanics | Elbow/Biceps Torque Problem #2

The video tutorial explores torque problems involving the elbow joint, focusing on calculating the force required by the biceps to hold a weight isometrically. It introduces additional variables, such as the weight of the forearm, and explains the process of solving the torque equation. The tutorial concludes with a discussion on the inefficiency of the bicep as a third-class lever and hints at future topics involving different angles and trigonometry.

What is the initial setup described for the basic torque problem involving the elbow joint?

• The elbow is extended and holding a weight statically.

• The elbow is extended and holding a weight dynamically.

• The elbow is flexed at 90 degrees and holding a weight isometrically.

• The elbow is flexed at 45 degrees and moving a weight up and down.

When considering the weight of the forearm, which additional concept is introduced?

• The center of mass of the shoulder.

• The center of mass of the hand.

• The center of gravity of the forearm.

• The center of rotation of the elbow.

What is the significance of the center of gravity in this torque problem?

• It is used to calculate the mass of the forearm.

• It determines the speed of rotation.

• It is irrelevant to the problem.

• It helps in calculating the torque due to the forearm.

What is the key formula used to solve torque problems in static equilibrium?

• Torque equals mass times acceleration.

• Torque equals force times distance.

• Torque equals energy divided by time.

• Torque equals velocity times time.

How is mass converted to force in the context of this problem?

• By subtracting 9.8 from the mass.

• By adding 9.8 to the mass.

• By multiplying the mass by 9.8.

• By dividing the mass by 9.8.

What is the calculated force exerted by the biceps to maintain static equilibrium?

• 3675 Newtons

• 98 Newtons

• 1225 Newtons

• 49 Newtons

What is the role of the bicep in maintaining static equilibrium?

• To exert no force.

• To exert a downward force.

• To exert an upward force.

• To exert a lateral force.

Why is the bicep considered an inefficient muscle in this context?

• It has a high mechanical advantage.

• It is a third-class lever with a low mechanical advantage.

• It is a first-class lever.

• It is a second-class lever with a high mechanical advantage.

What happens to the force exerted by the bicep when the weight of the forearm is considered?

• The force becomes zero.

• The force increases.

• The force remains the same.

• The force decreases.

What is the effect of changing the angle of the bicep on the torque problem?

• It has no effect on the problem.

• It eliminates the need for force calculations.

• It introduces more angles and requires trigonometry.

• It simplifies the problem.