Part II. Problem Solving. Answer the following questions. Your solutions must be

Question

Part II. Problem Solving. Answer the following questions. Your solutions must be numerical answer without the proper steps will NOT get clear and show all your work. A correct You MUST state the physieal principle or equation to use BEFORE substitut 1. (25 pts.) A pushing force F, 250 N is applied to a block of mass m = 50 kg at an angle = 30°. The block slides downward against a wall with a constant acceleration of magnitude a 4.0 m/s (see Figure). We want to determine the coefficient of kinetie friction between the block and the wall. 772 ni (6 pts.) Draw the free-body diagram for the block sliding down the wall. Illustrate the direction of the acceleration. a. for le b.)(19 pts.) Determine the coefficient of kinetic friction between the block and the wall. (Hints: Apply Newton's Second Law in the horizontal and vertical directions, separately Calculate the magnitude of the normal force and the magnitude of the kinetic friction.)

Explanation / Answer

Here, the normal force is provided by the horizontal component of the applied force and it is directed in the left direction.

so, R = Fcos30 = 250cos30 = 216.506 N

and the net force in vertical direction must be zero and so

mg - Fsin30 - ukR = ma

=> (50 x 9.8) - 125 - uk(216.506) = 50(4)

=> uk = 0.762

this is the coefficient of kinetic friction.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---