A flat (unbanked) curve on a highway has a radius of $170.0$ m. A car rounds the curve at a speed of $25.0$ m/s. What is the minimum coefficient of static friction that will prevent sliding?

The 'Giant Swing' at a county fair consists of a vertical central shaft with a number of horizontal arms attached at its upper end. Each arm supports a seat suspended from a cable $5.00$ m long, and the upper end of the cable is fastened to the arm at a point $3.00$ m from the central shaft (Fig. E$5.50$). Find the time of one revolution of the swing if the cable supporting a seat makes an angle of $30.0°$ with the vertical.

A $1125$-kg car and a $2250$-kg pickup truck approach a curve on a highway that has a radius of $225$ m. At what angle should the highway engineer bank this curve so that vehicles traveling at $65.0$ mi/h can safely round it regardless of the condition of their tires? Should the heavy truck go slower than the lighter car?

A small remote-controlled car with mass $1.60$ kg moves at a constant speed of $v=12.0$ m/s in a track formed by a vertical circle inside a hollow metal cylinder that has a radius of $5.00$ m (Fig. E$5.45$). What is the magnitude of the normal force exerted on the car by the walls of the cylinder at point $A$ (bottom of the track)?

In another version of the 'Giant Swing' (see Exercise $5.50$), the seat is connected to two cables, one of which is horizontal (Fig. E$5.51$). The seat swings in a horizontal circle at a rate of $28.0$ rpm (rev/min). If the seat weighs $255$ N and an $825$-N person is sitting in it, find the tension in each cable.

A small remote-controlled car with mass $1.60$ kg moves at a constant speed of $v = 12.0$ m/s in a track formed by a vertical circle inside a hollow metal cylinder that has a radius of $5.00$ m (Fig. E$5.45$). What is the magnitude of the normal force exerted on the car by the walls of the cylinder at point $B$ (top of the track)?

A small car with mass $0.800$ kg travels at constant speed on the inside of a track that is a vertical circle with radius $5.00$ m (Fig. E$5.45$). If the normal force exerted by the track on the car when it is at the top of the track (point $B$) is $6.00$ N, what is the normal force on the car when it is at the bottom of the track (point $A$)?