SPRING 2005

HOMOKINETICS II

ASSIGNMENT # 2

1. Given the mass or weight and the volume of each of the following objects, calculate the densities or specific weight.

OBJECT WEIGHT OR MASS VOLUME

A 50 kg 15.00 cm³

B 90 lb 12.00 in³

C 3 slugs 1.50 ft³

D 450 N 0.14 m³

E 45 kg 30.00 cm³

2. Two muscles develop tension simultaneously on opposite sides of a joint. Muscle A, attaching 3 cm from the axis of rotation at the joint exerts 250 N of force. Muscle B, attaching 2.5 cm from the joint axis, exerts 260 N of force. How much torque is created at the joint by each muscle?

3. A basketball player is dribbling and from his body weight there is a force of 500 N on

the L₁ vertebrae and a stress of 770 N/m². How much surface area is associated with

the lumbar vertebrae?