__bme 101 Lab 8: Forces and Torques__

__Lab 8: Forces and Torques__

**Introduction: **The goal of this lab is to understand different types of forces and torques that occur during muscle contraction about joints using the information from the muscle mechanics lab.

What is the equation for torque? What units are torque in, and what is torque defined as?

*bme 101 Lab 8: Forces and Torques*

*The equation is F*** ***** r , the unit is N*m. The tendency of a force to rotate an object about an axis**

Calculate the torque in the following scenarios.

T= 10*10=100 N.m | |

T=10*10*cos40=76.6 N.m | |

T=4*20*sin70=75.2 N.m |

**Problem: **Assuming the combination of both forearms and hands amounts to 6.00% of a human’s bodyweight, that the biceps is attached 5.5 cm below the elbow joint, and the center of mass of the forearm lies 16.0 cm from the elbow joint of a 38.0 cm forearm. As a group, generate a general equation for the force excreted on the forearm by the biceps if your mass is “M” kg and you wish to raise a “m” kg weight using your biceps muscle while your forearm is at any given angle theta below the horizontal. Then use your equation to create an excel sheet to solve the force in the biceps brachii for the following scenarios.

Equation:

Fb= [(3.73*cos (angle below horizontal) *dumbbell mass*) +(.047*body mass*cos (angle below horizontal)]/ (.055* cos (angle below horizontal)

Scenarios:

Screenshot of Excel sheet:

bme 101 Lab 8: Forces and Torques

**Post-Lab:**

- What about a force affects torque? Is there a certain aspect that is easiest to change in certain scenarios? Think about opening a fire hydrant, using a ratchet, or rowing a boat.

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- What are some examples of general equation applications? When would it be easier to create a general equation instead of calculating steps as you go.

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**bme 101 Lab 8: Forces and Torques**

**Conclusion (Follow Syllabus): **

The conclusion format and grading will be the same for each lab:

Review of topics learned in lab activity

What went well/unwell (1 of each)
/2pts. What would you change next time?

What Real world application of topics ?

How could the real-world application be improved/innovated and how would this produce an economic benefit?