A model airplane of mass 0.750 kg flies in a horizontal circle at the end of a 60.0-m control wire, with a speed of 35.0 m/s. Compute the tension in the wire if it makes a constant angle of 20.0° with the horizontal. The forces exerted on the airplane are the pull of the control wire, the gravitational force, and aerodynamic lift, which acts at 20.0° inward from the vertical as shown in Figure P6.71.

You are swinging a 0.25 kg water balloon vertically. The distance from your shoulder (acting as the center of rotation) and the water balloon is about 0.65 m. You estimate the water balloon is traveling at 7.0 m/s. At the very top of the circular path, how much force is your hand holding the water balloon? Enter absolute value. Hint: the water balloon is experiencing uniform circular motion.

At amusement parks, there is a popular ride where the floor of a rotating cylindrical room falls away, leaving the backs of the riders “plastered” against the wall. Suppose the radius of the room is 7.9 m and the coefficient of friction between the rider and the wall is 0.839, what is the minimum the safe speed of the wall for the rider not to drop when the floor falls away. Use g=9.8 m/s2.

A small ball is attached to one end of light rope that has a length of 4.0 m. The other end of the rope is attached to the ceiling. The ball is held with the rope horizontal and released from rest. The ball moves in the motion of an arc of the circle. When the ball is at its lowest point, with the rope vertical, the tesion of the rope is 15.5 N. What is the mass of the ball?

An air puck of mass 0.30 kg is tied to a string and allowed to revolve in a circle of radius 1.3 m on a frictionless horizontal table. The other end of the string passes through a hole in the center of the table, and a mass of 1.5 kg is tied to it. The suspended mass remains in equilibrium while the puck on the tabletop revolves. (a) What is the tension in the string? N (b) What is the force causing the centripetal acceleration on the puck? (c) What is the speed of the puck? m/s Need Help? Read It

A puck of mass m = 1.10 kg slides in a circle of radius r = 19.0 cm on a frictionless table while attached to a hanging cylinder of mass M = 4.10 kg by a cord through a hole in the table. What speed keeps the cylinder at rest?

A 1.5-lb slider is propelled upward at A along the fixed curved bar which lies in a vertical plane. If the slider is observed to have a speed of 10.6 ft/sec as it passes position B, determine (a) the magnitude N of the force exerted by the fixed rod on the slider and (b) the rate v at which the speed of the slider is changing (positive if speeding up, negative if slowing down). Assume that friction is negligible. 29 2.8' Answers: N = Ib i ft/sec?

A small block of mass 1.26 kg slides without friction on a horizontal table. Initially it moves in a circle of radius Ro = 0.6 m with a speed 1.5 m/s. It is held in its path by a string that passes through a small hole at the center of the circle. The string is then pulled down a distance of 0.12 m.( Ro - R = 0.12 m.) It is pulled so slowly that the object continues to move in a circle of continually decreasing radius. 1) While the string in pulling in the block, which of the following qualities of the block is conserved (circle all that are correct): a) Rotational kinetic energy (b) Angular momentum c) Linear momentum d) Mechanical energy e) None of the above √/2) What is the final linear speed of the block (in m/sec)? 1.5 m/sec (3) How much work was done by the force that pulled on the string?0.915

A 59.0-kg ice skater is moving at 4.07 m/s when she grabs the loose end of a rope, the opposite end of which is tied to a pole. She then moves in a circle of radius 0.810 m around the pole. red (a) Determine the magnitude of the force exerted by the horizontal rope on her arms. kN (b) Compare this force with her weight. Frope %3D W Need Help? Read It

You have applied for a great summer job working with a special effects team at a movie studio.  As part of your interview you have been asked to evaluate the design for a stunt in a new Indiana Jones production.  A large spherical boulder starts from rest and rolls down an inclined track.  At the bottom, the track curves up into a vertical circle so that the boulder can roll around on the inside of the circle and come back to ground level.  It is important that the boulder not fall off the track at the top of the circle and crush the star standing below.  You have been asked to determine the relationship between the heights of the boulder’s starting point on the ramp (measured from the center of the boulder) and the maximum radius of the circular part of the track.  You can determine the mass and the radius of the boulder should you need to know them.  You have been told that the moment of inertia of a sphere is 2/5 that of a ring of the same mass and radius.  After some thought you…