Physics acceleration and tension question

Question

A 10-kg mass is laying flat on a table with a string attached that runs over the edge of the table via a pulley. You have a 20-kg mass attached to the string that is hanging off the table. The 20-kg mass is accelerating downward with the same acceleration horizontally that the 10-kg mass has. What is that acceleration, and what is the tension of the string?

Answer 1

Doing a force diagram the forces acting on the mass on the table is tension in the cord and the forces acting on the hanging mass are the tension and weight of the mass. Hence the equations of motion are m1a=T and m2a=m2g-T. Using the equations gives m2a= m2g -m1a. Therefore a(m1+m2)=m2g. Then a = m2g/(m1 +m2). Using the parameters given in the problem a=20*9.8/30. Doing the calculation a= 6.53 m/s^2.

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