Linear Momentum and Second Law of Motion: Practice Problem & Solution

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Linear Momentum and Second Law of Motion. Understanding the underlying formula is key to arriving at the correct answer below:

Horizontal momentum remains unchanged. Initial vertical momentum \( P_{iy} = m v \sin 45^{\circ} = m v / \sqrt{2} \). Final vertical momentum \( P_{fy} = -m v \sin 45^{\circ} = -m v / \sqrt{2} \). Change in vertical momentum \( \Delta P_y = P_{fy} - P_{iy} = -\sqrt{2} mv \). The magnitude of the change in momentum is \( \sqrt{2} mv \).