Brian stands on one foot, and then lifts his heel off the floor by flexing his calf muscles. His Achilles' tendon connects the gastrocnemius and soleus (calf) muscles at a 75-degree angle to the calcaneus (heel), five cm from the axis, where his tibia (shin) joins with the callus (ankle). His metatarsals (toes) end fifteen em from this axis, with foot tilted 40-degrees from the ground. a.) Brian's mass m = 50kg is all held up by a normal force applied at his toes. How much torque does this force apply about the axis of his ankle? b.) What is the magnitude of the force Brians calf is exerting on his heel? Hint: Torques... about Ankle axis... c.) What are the magnitude and direction of the force that Brians tibia is applying to the ankle?
Angular speed, acceleration and displacement
Angular acceleration is defined as the rate of change in angular velocity with respect to time. It has both magnitude and direction. So, it is a vector quantity.
Angular Position
Before diving into angular position, one should understand the basics of position and its importance along with usage in day-to-day life. When one talks of position, it’s always relative with respect to some other object. For example, position of earth with respect to sun, position of school with respect to house, etc. Angular position is the rotational analogue of linear position.
Brian stands on one foot, and then lifts his heel off the floor by flexing his calf muscles.
His Achilles' tendon connects the gastrocnemius and soleus (calf) muscles at a 75-degree angle to the calcaneus (heel), five cm from the axis, where his tibia (shin) joins with the callus (ankle). His metatarsals (toes) end fifteen em from this axis, with foot tilted 40-degrees from the ground.
a.) Brian's mass m = 50kg is all held up by a normal force applied at his toes.
How much torque does this force apply about the axis of his ankle?
b.) What is the magnitude of the force Brians calf is exerting on his heel?
Hint: Torques... about Ankle axis...
c.) What are the magnitude and direction of the force that Brians tibia is applying to the ankle?
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