Exam 5: The Laws of Motion

A 2.0-kg block slides on a frictionless 15° inclined plane. A force acting parallel to the incline is applied to the block. The acceleration of the block is 1.5 m/s² down the incline. What is the applied force?

Exhibit 5-1 A 2.30 kg mass is suspended from the ceiling and a 1.70 kg mass is suspended from the 2.30 kg mass, as shown. The tensions in the strings are labeled and . Use this exhibit to answer the following question(s). -Refer to Exhibit 5-1. A hand exerts an upward force of 6.70 N on the 1.70 kg mass. The magnitudes of the tensions are

Two identical springs with spring constant 50 N/m support a 5.0 N weight as in the picture below. What is the tension in spring A?

The three blocks shown are released from rest and are observed to move with accelerations that have a magnitude of 1.5 m/s². What is the magnitude of the friction force on the block that slides horizontally? Disregard any pulley mass or friction in the pulley and let M = 2.0 kg.

In the figure, if the tension in string 1 is 34 N and the tension in string 2 is 24 N, what is the mass of the object shown? ​ ​

A 5.0-kg mass sits on the floor of an elevator that has a downward acceleration of 1.0 m/s². On top of the 5.0-kg mass is an object of unknown mass. The force of the elevator on the 5.0-kg mass is 80 N up. Determine the unknown mass.

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 book is placed on a chair. Then a videocassette is placed on the book. The floor exerts a normal force

The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes an angle with the ground. When a force of magnitude F is applied to each box in a direction parallel to the surface it is on, upwards on the box on the ramp, neither box moves. Which statement comparing the friction force on the box on the level, f_L, to the friction force on the box on the ramp, f_R, is correct?

Two blocks are accelerated across a horizontal frictionless surface as shown. Frictional forces keep the two blocks from sliding relative to each other, and the two move with the same acceleration. If F = 1.2 N and M = 1.0 kg, what is the horizontal component (frictional force) of the force of the large block on the small block?

If α = 40°, β = 60°, and M = 4.0 kg, determine the tension in string 1.

A book is placed on a chair. Then a videocassette is placed on the book. The floor exerts a normal force

A chair is placed on a rug. Then a book is placed on the chair. The floor exerts a normal force

A 3.0-kg block moves up a 40° incline with constant speed under the action of a 26-N force acting up and parallel to the incline. What magnitude force must act up and parallel to the incline for the block to move down the incline at constant velocity?

A 70-kg stunt artist rides in a rocket sled which slides along a flat inclined surface. At an instant when the sled's acceleration has a horizontal component of 6.0 m/s² and a downward component of 2.8 m/s², what is the magnitude of the force on the rider by the sled?

If F = 4.0 N and m = 2.0 kg, what is the magnitude a of the acceleration for the block shown below? The surface is frictionless.

Exhibit 5-1 A 2.30 kg mass is suspended from the ceiling and a 1.70 kg mass is suspended from the 2.30 kg mass, as shown. The tensions in the strings are labeled and . Use this exhibit to answer the following question(s). -Refer to Exhibit 5-1. The string supporting the 1.70 kg mass is cut. The magnitudes of the tension in string 1 before and after string 2 is cut are

Two blocks in contact with each other are pushed to the right across a rough horizontal surface by the two forces shown. If the coefficient of kinetic friction between each of the blocks and the surface is 0.30, determine the magnitude of the force exerted on the 2.0-kg block by the 3.0-kg block.

Two blocks connected by a string are pulled across a horizontal surface by a force applied to one of the blocks, as shown. The coefficient of kinetic friction between the blocks and the surface is 0.25. If each block has an acceleration of 2.0 m/s² to the right, what is the magnitude F of the applied force?

Exhibit 5-2 A 4.00 kg block is suspended from the roof of an elevator. A 2.00 kg block is suspended from the 4.00 kg block. The tensions in strings 1 and 2 are labeled and . Use this exhibit to answer the following question(s). -Refer to Exhibit 5-2. When the elevator accelerates downwards with an acceleration of 2.20 m/s², the magnitudes of and are