Robotics The Tech

Classroom Activities

Activity #5: Calculating Power

At the beginning of the gear activity section, we discussed the mathematical formula for torque ( t = rF ). In this activity, we will introduce additional variables for distance of a circle and revolutions per second. A tangential force at a crank radius of r will move through a distance of 2pi @ The Tech x r each time the shaft makes one complete revolution. This movement creates a certain amount of work as described as:

W = F x 2pi @ The Tech x r
Adding the torque equation to the work equation, we come up with:
W = 2pi @ The Tech x t
This can then be transferred to the power equation which is:
P = 2pi @ The Tech x t x f
Where f is equal to the motor's speed in revolutions per second.

pencil and paper, calculator

Calculate the power supplied by a motor running at 3400 rpm while delivering a torque of 800 foot lbs.

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