Exam 5: More Applications of Newtons Laws

A 30-kg child rides on a circus Ferris wheel that takes her around a vertical circular path with a radius of 20 m every 22 s.What is the magnitude of the resultant force on the child at the highest point on this trajectory?

A 2.0-kg block slides on a rough horizontal surface.A force (P = 6.0 N)is applied to the block as shown.The magnitude of the block's acceleration is 1.2 m/s².What is the magnitude of the force of friction acting on the block?

In the figure shown,the coefficient of kinetic friction between the block and the incline is 0.40.What is the magnitude of the acceleration of the suspended block as it falls? Disregard any pulley mass or friction in the pulley.

An airplane flies in a horizontal circle of radius 500 m at a speed of 150 m/s.If the radius were changed to 1 000 m,but the speed remained the same,by what factor would its centripetal acceleration change?

A 4.0-kg mass attached to the end of a string swings in a vertical circle of radius 2.0 m.When the string makes an angle of 35 $\degree$ with the vertical as shown,the speed of the mass is 5.0 m/s.At this instant what is the magnitude of the force the string exerts on the mass?

A student is sitting on the right side of a school bus when it makes a right turn.We know that the force of gravity acts downwards and a normal force from the seat acts upwards.If the student stays in place when the bus turns,we also know that there must be

A 4.0-kg block is pushed up a 36 $\degree$ incline by a force of magnitude P applied parallel to the incline.When P is 31 N,it is observed that the block moves up the incline with a constant speed.What value of P would be required to lower the block down the incline at a constant speed?

A car travels around an unbanked highway curve (radius 0.15 km)at a constant speed of 25 m/s.What is the magnitude of the resultant force acting on the driver,who weighs 0.80 kN?

A race car travels 40 m/s around a banked (45 $\degree$ with the horizontal)circular (radius = 0.20 km)track.What is the magnitude of the resultant force on the 80-kg driver of this car?

A 1.8-kg block is released from rest at the top of a rough 30 $\degree$ inclined plane.As the block slides down the incline,its acceleration is 3.0 m/s² down the incline.Determine the magnitude of the force of friction acting on the block.

A 3.0-kg block slides on a rough horizontal surface.A force of 8.0 N acting parallel to the surface is applied to the block.The coefficient of kinetic friction between the block and the surface is 0.15.What is the magnitude of the block's acceleration?

A 4.0-kg block slides down a 35 $\degree$ incline at a constant speed when a 16-N force is applied acting up and parallel to the incline.What is the coefficient of kinetic friction between the block and the surface of the incline?

A stunt pilot weighing 0.70 kN performs a vertical circular dive of radius 0.80 km.At the bottom of the dive,the pilot has a speed of 0.20 km/s which at that instant is not changing.What force does the plane exert on the pilot?

Two small cylindrical plastic containers with flat bottoms are placed on a turntable that has a smooth flat surface.Canister A is empty;canister B contains lead shot.Each canister is the same distance r from the center.The coefficient of static friction between the canisters and the turntable is $\mu$ _s.When the speed of the turntable is gradually increased,

A rock attached to a string swings in a vertical circle.Which free body diagram could correctly describe the force(s)on the rock when it is at the lowest point?

Frank says that if you release the string when swinging a ball in a horizontal circle,the ball flies out in the radial direction defined by the string at the instant you release the ball.John says that it flies out along a tangent line perpendicular to the string,and that it then drops straight down to the ground.Which one,if either,is correct?

In the figure,the coefficient of kinetic friction between the surface and the larger block is 0.20,and the coefficient of kinetic friction between the surface and the smaller block is 0.30.If F = 10 N and M = 1.0 kg,what is the tension in the connecting string?

A roller-coaster car has a mass of 500 kg when fully loaded with passengers.At the bottom of a circular dip of radius 40 m (as shown in the figure)the car has a speed of 16 m/s.What is the magnitude of the force of the track on the car at the bottom of the dip?

The frictional force of the floor on a large suitcase is least when the suitcase is

A block is pushed across a horizontal surface by the force shown.If the coefficient of kinetic friction between the block and the surface is 0.30,F = 20 N, $\theta$ = 30 $\degree$ ,and M = 3.0 kg,what is the magnitude of the acceleration of the block?