© Copyright, Department of Physics, University of Illinois at Urbana-Champaign

Two Blocks on an Incline

Two blocks are positioned on two sides of an incline as shown above. Both blocks have mass 0.7 kg. The two blocks are connected by a massless * string passing over an ideal pulley*. The angles of the incline are q 1 = 30 degrees and q 2 = 60 degrees . The coefficient of kinetic friction is m = 0.02.
Define acceleration of the block A on the left to be positive if it goes up the plane, and negative if it goes down the plane. What is the acceleration of the block A on the left side ? If you type in the expression for the acceleration, use angles in the units of degrees, not radians.
Assume gravity due to Earth, with the gravitational constant g=9.81 m/sec2.

* An 'ideal' pulley is frictionless and massless. The 'massless string' also cannot stretch or shrink. These simplifying assumptions allow us to focus on fundamental aspects of the problem without getting bogged down with (less fundamental) details. Perhaps you've heard the expression 'Let's take a spherical cow'!

aA = m/s2