Your grandmother enjoys creating pottery as a hobby. She uses a potter's wheel, which is a stone disk of radius R=0.560 m and mass M=100 kg . In operation, the wheel rotates at 40.0 rev/min. While the wheel is spinning, your grandmother works clay at the center of the wheel with her hands into a pot-shaped object with circular symmetry. When the correct shape is reached, she wants to stop the wheel in as short a time interval as possible, so that the shape of the pot is not further distorted by the rotation. She pushes continuously with a wet rag as hard as she can radially inward on the edge of the wheel and the wheel stops in 6.00 s.
(a) You would like to build a brake to stop the wheel in a shorter time interval, but you must determine the coefficient of friction between the rag and the wheel in order to design a better system. You determine that the maximum pressing force your grandmother can sustain for 6.00 s is 50.0 N.
(b) What If? If your grandmother instead chooses to press down on the upper surface of the wheel a distance r=0.250 m from the axis of rotation, what is the force (in N ) needed to stop the wheel in 6.00 s? Assume that the coefficient of kinetic friction between the wet rag and the wheel remains the same as before. (Enter the magnitude.)
A potter's wheel having a radius of 0.561 m and a moment of inertia of 12.5 kg⋅⋅m22 is rotating freely at 53.7 rev/min. The potter can stop the wheel in5.22 s by pressing a wet rag against the rim and exerting a radially inward force of 68.2 N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.
A potter's wheel having a radius 0.49 m and a moment of inertia of 12.4 kg · m2 is rotating freely at 46 rev/min. The potter can stop the wheel in 5.5 s by pressing a wet rag against the rim and exerting a radially inward force of 71 N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.
A potter's wheel having a radius 0.45 m and a moment of inertia of 10.3 kg · m2 is rotating freely at 46 rev/min. The potter can stop the wheel in 6.5 s by pressing a wet rag against the rim and exerting a radially inward force of 73 N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.
A potter's wheel having a radius of 0.500 m and mass 45.0 kg is rotating freely at 50.0 rev/min in a clockwise direction. The potter can stop the wheel by pressing a wet rag against the outside rim of the wheel and exerting a radially inward force of 70.0 N. Since this force is in the radial direction, it alone cannot cause the wheel to slow its spinning. What can happen, however, is that a normal force can result from...
A potter's wheel having a radius 0.53 m and a moment of inertia 12.1 kg m is rotating freely at si rev/min. The potter can stop the wheel 25 dy pressing weragaan a radially inward force of 71 N. Find the effective coeficient of kinetic friction between the wheel and the wet rag anderer Need Help? Read Teo Tutor
10. + 0/3 points | Previous Answers SerPSET9 12.P.021. My Notes + Ask Your Teacher John is pushing his daughter Rachel in a wheelbarrow when it is stopped by a brick 8.00 cm high (see the figure below). The handles make an angle of a = 20.0° with the ground. Due to the weight of Rachel and the wheelbarrow, a downward force of 405 N is exerted at the center of the wheel, which has a radius of 15.0 cm....