a child is playing in a park on rotating cylinder of radius, r, is set in rotation at an angular speed. The base of the cylinder is slowly moved away, leasing the child's suspended against the wall in a vertical position. What ia the minimum coefficient of friction between the child's clothing and wall is needed to prevent it from falling?

Air flows upward in the wick of a lantern because of the liquid property called

Wavelength, frequency, and energy are related. what happens to a wave as it’s wavelength gets shorter?

Aperson gives a shopping cart an initial push along a horizontal floor to get it moving, and then lets go. the cart travels forward along the floor, gradually slowing as it moves. consider the horizontal force(s) on the cart while it is moving forward and slowing. which of the following statements is correct? (a) both a forward and a backward force are acting on the cart, but the forward force is larger. (b) only a forward force is acting which diminishes with time. (c) both a forward and a backward force are acting on the cart, but the backward force is larger. (d) only a backward force is acting, no forward force.