Block, Pulley, Friction System Dynamics | Symbolic Physics (AP Free Response, College 1)
*I used u and uk as interchangeable for the coefficient of kinetic friction. Sorry about that! k is a subscript, not a variable.
This problem is based on the following AP Physics Free Response from 1976(!). I modified it to focus on the algebraic format that the modern AP prefers. The purpose of this series of videos is to spend as much time as I can walking you through the algebraic solutions to physics problems, in an effort to bridge the gap between student's mathematical fluency and conceptual understanding.
1979B2. A 10-kilogram block rests initially on a table as shown in cases I and II above. The coefficient of sliding friction between the block and the table is 0.2. The block is connected to a cord of negligible mass, which hangs over a massless frictionless pulley. In case I a force of 50 newtons is applied to the cord. In case II an object of mass 5 kilograms is hung on the bottom of the cord. Use g = 10 meters per second squared.
a. Calculate the acceleration of the 10-kilogram block in case I.
b. On the diagrams below, draw and label all the forces acting on each block in case II
c. Calculate the acceleration of the 10-kilogram block in case II.
This video features: A block of mass M rests initially on a table as shown in cases I and II below. The coefficient of kinetic friction between the block and the table is u. The block is connected to a cord of negligible mass, which hangs over a massless frictionless pulley. In case I a force with magnitude F newtons is applied to the cord. In case II an object of mass m kilograms is hung on the bottom of the cord.
a)Calculate the acceleration of the block in case I.
b)Calculate the acceleration of the block of mass M in case II.