Math Help - Force pushing through two objects

In Figure 5-50a, a constant horizontal force a is applied to block A, which pushes against block B with a 18.0 N force directed horizontally to the right. In Figure 5-48b, the same force is applied to block B; now block A pushes on block B with a 11.0 N force directed horizontally to the left. The blocks have a combined mass of 12.0 kg. What are the magnitudes of (a) their acceleration in Figure 5-50a and (b) force a?

Fig. 5-50
Problem 52.

Originally Posted by BiGpO6790

In Figure 5-50a, a constant horizontal force a is applied to block A, which pushes against block B with a 18.0 N force directed horizontally to the right. In Figure 5-48b, the same force is applied to block B; now block A pushes on block B with a 11.0 N force directed horizontally to the left. The blocks have a combined mass of 12.0 kg. What are the magnitudes of (a) their acceleration in Figure 5-50a and (b) force a?

Fig. 5-50

Problem 52.

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