[{"title": "Newton's Second Law", "content": "A 10 kg box is pushed with a force of 50 N. What is its acceleration? F = ma → 50 = 10 × a → a = 50/10.", "solution": "a = 5 m/s²"}, {"title": "Newton's Third Law", "content": "A swimmer pushes water backward (action). The water pushes the swimmer forward (reaction). This is why swimming works.", "solution": "Action and reaction forces are equal in magnitude and opposite in direction."}]