Exam 5: Applying Newtons Laws

Jason takes off from rest across level water on his jet-powered skis.The combined mass of Jason and his skis is (the mass of the fuel is negligible).The skis have a thrust of and a coefficient of kinetic friction on water of 0.10.Unfortunately,the skis run out of fuel after only .What is Jason's top speed?

A 4.00-kg box sits atop a 10.0-kg box on a horizontal table.The coefficient of kinetic friction between the two boxes and between the lower box and the table is 0.600,while the coefficient of static friction between these same surfaces is 0.800.A horizontal pull to the right is exerted on the lower box,as shown in the figure,and the boxes move together.What is the friction force on the UPPER box?

A 20.0-N box rests on a 50.0-N box on a perfectly smooth horizontal floor.When a horizontal pull to the right is exerted on the lower box (see figure),both boxes move together.Find the magnitude and direction of the net external force on the upper box.

Block A of mass 5.0 kg and block X are attached to a rope which passes over a pulley,as shown in the figure.An 80-N force P is applied horizontally to block A,keeping it in contact with a rough vertical face.The coefficients of static and kinetic friction between the wall and block A are μ_s = 0.40 and μ_k = 0.30.The pulley is light and frictionless.The mass of block X is adjusted until block A moves upward with an acceleration of 1.6 m/s².What is the mass of block X?

You push downward on a box at an angle 25° below the horizontal with a force of .If the box is on a flat horizontal surface for which the coefficient of static friction with the box is 0.76,what is the mass of the heaviest box you will be able to move?

The figure shows two forces acting at right angles on an object.They have magnitudes and .What third force will cause the object to be in equilibrium (acceleration equals zero)?

A string is attached to the rear-view mirror of a car.A ball is hanging at the other end of the string.The car is driving around in a circle,at a constant speed.Which of the following lists gives all of the forces directly acting on the ball?

A car travels at a steady 40.0 m/s around a horizontal curve of radius 200 m.What is the minimum coefficient of static friction between the road and the car's tires that will allow the car to travel at this speed without sliding?

An object weighing 4.00 N falls from rest subject to a frictional drag force given by ,where v is the speed of the object and What terminal speed will this object approach?

Future space stations will create an artificial gravity by rotating.Consider a cylindrical space station 390 m diameter rotating about its central axis.Astronauts walk on the inside surface of the space station.What rotation period will provide "normal" gravity?

Suppose a highway curve is properly banked to eliminate friction for a speed of 45 mph.If your tires were bald and you wanted to avoid sliding on the road,you would have to drive

A 6.0 kg box slides down an inclined plane that makes an angle of 39° with the horizontal.If the coefficient of kinetic friction is 0.19,at what rate does the box accelerate down the slope?

In the figure,a block of mass M hangs at rest.The rope that is fastened to the wall is horizontal and has a tension off 52 N.The rope that is fastened to the ceiling has a tension of and makes an angle θ with the ceiling.What is the angle θ?

The figure shows two 1.0 kg-blocks connected by a rope.A second rope hangs beneath the lower block.Both ropes have a mass of 250 g.The entire assembly is accelerated upward at 2.3 m/s² by force .What is the tension at the top end of rope 1?

The figure shows two wires that are tied to a 710 g mass that revolves in a horizontal circle at a constant speed of .What is the tension in the upper wire?

A person on a sled coasts down a hill and then goes over a slight rise with speed .The top of this rise can be modeled as a circle of radius 4.1 m.The sled and occupant have a combined mass of 110 kg.If the coefficient of kinetic friction between the snow and the sled is 0.10,what friction force is exerted on the sled by the snow as the sled goes over the top of the rise?

Three objects are connected by massless wires over a massless frictionless pulley as shown in the figure.The tension in the wire connecting the and objects is measured to be .What is the tension in wire A?

A 4.00-kg block rests on a 30.0° incline as shown in the figure.If the coefficient of static friction between the block and the incline is 0.700,what magnitude horizontal force F must act on the block to start it moving up the incline?

A 600-kg car traveling at is going around a curve having a radius of 120 m that is banked at an angle of 20°. (a)Is the curve properly banked for the car's speed? (b)What is the minimum coefficient of static friction required between the road and the car's tires so the car does not skid?

Two blocks are connected by a string that goes over an ideal pulley as shown in the figure and pulls on block A parallel to the surface of the plane.Block A has a mass of 3.00 kg and can slide along a rough plane inclined 30.0° to the horizontal.The coefficient of static friction between block A and the plane is 0.400.What mass should block B have in order to start block A sliding up the plane?