Your team is prototyping a simple braking system for your model car. The 3.4 kg wheel with a radius of r = rad 0.15 m is rotating at w 18. A servo motor can apply a variable force F, which in its first two seconds of operation is equal to F10t N and afterwards is equivalent to a constant force of F = 20 N . If the coefficient of kinetic friction between the braking arm and the wheel is 0.2, determine the time needed for the wheel to come to a full stop. The point of contact P between the wheel and the arm is a distance r = -0.2 + 0.26 m from point A. The force of the servo motor is applied at exactly half of the horizontal distance to A from the point of contact. Assume the wheel can be treated as a disk and that the braking arm is massless.

Your team is prototyping a simple braking system for your model car. The 3.4 kg wheel with a radius of r = rad 0.15 m is rotating at w 18. A servo motor can apply a variable force F, which in its first two seconds of operation is equal to F10t N and afterwards is equivalent to a constant force of F = 20 N . If the coefficient of kinetic friction between the braking arm and the wheel is 0.2, determine the time needed for the wheel to come to a full stop. The point of contact P between the wheel and the arm is a distance r = -0.2 + 0.26 m from point A. The force of the servo motor is applied at exactly half of the horizontal distance to A from the point of contact. Assume the wheel can be treated as a disk and that the braking arm is massless.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.60P: The force P applied to the brake handle enables the band brake to reduce the angular speed of a...

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