1. The problem statement, all variables and given/known data A horizontal force F is applied to a frictionless pulley of mass m2. The horizontal surface is smooth. Show that the acceleration of the block of mass m1 is twice the acceleration of the pulley. LOOKS LIKE THIS: http://cnx.org/content/m14060/latest/npq1.gif But WITHOUT block B and its string. 2. Relevant equations F=ma 3. The attempt at a solution I drew separate force diagrams for m1 (the block) and m2 (the pulley. In the x direction, the block is only being acted on by T1 going in the pos. x direction. In the x direction, the pulley is being acted on by 2T1 and F. 2T1 is going in the neg. x direction. F, the opposite. I have to show that a1= 2a2 So: The pulley is in equilibrium: F-2T1 = 0 m2a2 - 2(m1a1)=0 . . .and I don't know where to go from here. . . .I can't eliminate mass. . . Thank you in advance!