|MadSci Network: Physics|
The net torque about any point in the rollerblader must be zero if the rollerblader is not to fall over. If the torque is computed about his center of gravity, then the torque caused by the normal force of the ground up on his wheeels is balanced by the torque due to inward force of static friction of the ground on his wheels. If these torques are computed about the contact point of the wheels on the ground, however, there seems to be a non-zero, net torque due to his weight since the normal and static friction forces act through the contact point and would not contribute to the torque about this point. The moment of inertia of the wheels negligable. How can there be a net torque about the contact point and none about the cg?
Re: Why doesn't a rollerblader leaning into a tight turn fall over?
Try the links in the MadSci Library for more information on Physics.