The figure below represents the a ball thrown at an angle 45°
The momentum takes places in y direction only because the change in velocity in x direction is zero. The change in the momentum of the ball is, ΔP=(Py)final−(Py)initial ΔP=(m√(v‌cos‌45°)2+2gh)−(mv‌cos‌45°) ΔP=(0.2√√10‌cos‌45°+2×10×(−1))−(0.2×√10‌cos‌45°) ΔP=−1−