Exam 5: Applying Newtons Laws

Two boxes are connected by a weightless cord running over a very light frictionless pulley as shown in the figure.Box A,of mass 8.0 kg,is initially at rest on the top of the table.The coefficient of kinetic friction between box A and the table is 0.10.Box B has a mass of 15.0 kg,and the system begins to move just after it is released. (a)Draw the free-body diagrams for each of the boxes,identifying all of the forces acting on each one. (b)Calculate the acceleration of each box. (c)What is the tension in the cord?

A 4.00-kg block rests between the floor and a 3.00-kg block as shown in the figure.The 3.00-kg block is tied to a wall by a horizontal rope.If the coefficient of static friction is 0.800 between each pair of surfaces in contact,what horizontal force F must be applied to the block to make it move?

Engineers are designing a curved section of a highway.If the radius of curvature of the curve is at what angle should the curve be banked so that a car traveling at 29.0 m/s will stay on the road without the aid of frictional forces?

A 150-N box is being pulled horizontally in a wagon accelerating uniformly at .The box does not move relative to the wagon,the coefficient of static friction between the box and the wagon's surface is 0.600,and the coefficient of kinetic friction is 0.400.The friction force on this box is closest to

The figure shows two wires tied to a 3.3 kg sphere that revolves in a horizontal circle at constant speed.At this particular speed the tension is the SAME in both wires.What is the tension?

A box is sliding down an incline tilted at a 12.0° angle above horizontal.The box is initially sliding down the incline at a speed of 1.50 m/s.The coefficient of kinetic friction between the box and the incline is 0.340.How far does the box slide down the incline before coming to rest?

A box slides down a frictionless plane inclined at an angle θ above the horizontal.The gravitational force on the box is directed

A child on a sled starts from rest at the top of a 15° slope.If the trip to the bottom takes how long is the slope? Assume that frictional forces may be neglected.

A packing crate rests on a horizontal surface.It is acted on by three horizontal forces: 600 N to the left,200 N to the right,and friction.The weight of the crate is 400 N.If the 600-N force is removed,the resultant force acting on the crate is

A factory robot drops a 10 kg computer onto a conveyor belt running at 3.1 m/s.The materials are such that μ_s = 0.50 and μ_k = 0.30 between the belt and the computer.How far is the computer dragged before it is riding smoothly on the belt?

A driver in a car traveling at slams on the brakes and skids to a stop.If the coefficient of friction between the tires and the horizontal road is 0.80,how long will the skid marks be?

Suppose the force of the air drag on an object is proportional to the speed of the object and in the direction opposite the object's velocity.If you throw an object upward,the magnitude of its acceleration is greatest

The figure shows two forces,each of magnitude 4.6 N,acting on an object.The angle between these forces is 40°,and they make equal angles above and below the horizontal.What third force will cause the object to be in equilibrium (acceleration equals zero)?

A woman is straining to lift a large crate,without success because it is too heavy.We denote the forces on the crate as follows: P is the upward force the woman exerts on the crate,C is the vertical contact force exerted on the crate by the floor,and W is the weight of the crate.How are the magnitudes of these forces related while the woman is trying unsuccessfully to lift the crate?

A system comprising blocks,a light frictionless pulley,a frictionless incline,and connecting ropes is shown in the figure.The 9.0-kg block accelerates downward when the system is released from rest.The tension in the rope connecting the block and the block is closest to