Two blocks of masses 20 kg and 9.0 kg are connected together by a light string and rest on a frictionless level surface.Attached to the 9.0-kg mass is another light string,which a person uses to pull both blocks horizontally.If the two-block system accelerates at 0.80 m/s²,what is the tension in the second string attached to the 9.0-kg mass? A)23 N B)14 N C)16 N D)7.2 N E)25 N

Question

Quizplus · Accepted Answer

Explanation:The tension in the string attached to the 9.0-kg mass is equal to the force applied by the person minus the force of friction between the blocks and the surface. The force of friction is zero because the surface is frictionless. Therefore, the tension in the string is equal to the force applied by the person, which is:$$F = ma = (20 kg + 9.0 kg)(0.80 m/s^2) = 23 N$$

Two Blocks of Masses 20 Kg and 9