How would I go about solving this Newtonian problem?
A truck is going around a circular track of radius 72m, banked at 60degrees. A spider rests on the inside wall of the truck. The coefficient of static friction b/w truck wall and spider is .91. Find the max speed that the truck can have before the spider begins to slip down wall.
I attempted using the reference frame of the spider inside the truck and resolving all forces acting on it, and equating it to the centripetal force of course, but I arrive at the supposedly wrong answer.
The spider is the small circle inside the rectangle in the attachment.