

Photograph at the top shows arm model in neutral force configuration
Force applied by the biceps (lower left), pulling up with the hand: Apply 2.5 kg to the biceps cable to support the unloaded forearm. The forearm may be kept at equilibrium by the simultaneous addition of masses in the ratio of 10:1 at the biceps and at the hand. The torques are balanced almost independently of the angular position of the arm.
Force applied to the triceps (lower right), pushing down with the hand: Hang the spring scale between the top hook and the hand hook, and attach the hanger to the triceps cable. Add masses to the hanger to determine how much force in the triceps is necessary to push down with the force read on the scale.
Demonstrate that forces in one dimension add algebraically Read More
Show that the sum of forces exerted on the mass by the scales is constant Read More
Demonstrate equilibrium of forces Read More
Show addition of forces along a line Read More
Demonstrate equilibrium of forces Read More
Demonstrate equilibrium of forces Read More
Develop a feel for equilibrium of forces on a large scale Read More
Demonstrate vector addition of forces Read More
Introduce the concept of torque Read More
Introduce the concept of torque Read More
Demonstrate that equilibrium of forces is an insufficient condition for static equilibrium Read More
Demonstrate equilibrium of torques Read More
Demonstrate balanced torques Read More
Demonstrate balanced torques Read More
Verify the equation for torques when the center of mass is outside the object Read More
Demonstrate equilibrium of torques Read More
Demonstrate equilibrium of torques Read More
Demonstrate a paradox in equilibrium of forces and torques Read More
Model the forces occurring in the arm Read More
Demonstrate a crane boom Read More