A rope pulls on the lower block in the figure with a tension ...

[colton]

A rope pulls on the lower block in the figure with a tension force of 20 N. The coefficient of kinetic friction between the lower block and the surface is 0.16.
 
  The coefficient of kinetic friction between the lower block and the upper block is also 0.16. The pulley has no appreciable mass or friction. What is the acceleration of the 2.0 kg block?
 
  A) 4.1 m/s2
  B) 5.1 m/s2
  C) 8.4 m/s2
  D) 9.2 m/s2

Question 2

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?
  What will be an ideal response?

[lkoler]

Answer to Question 1

Answer: A

Answer to Question 2

Answer:
(a) Box A is acted on by the downward force of gravity, the upward normal force due to the table top, the tension in the string toward the right, and the force of friction due to the table top toward the left. Box B is acted on by the downward force of gravity and the upward tension of the string.
(b) 6.1 m/s2
(c) 56 N

[colton]

Great answer, keep it coming

[flexer1n1]

Gracias!