Hey guys, I'm currently taking the first physics course right now (calculus-based physics), but it's not going as smoothly as I would've hoped. Anyways, here's one of the many questions I shall be posing on the forum: A baseball approaches home plate at a speed of 47.0 m/s, moving horizontally just before being hit by a bat. The batter hits a pop-up such that after hitting the bat, the baseball is moving at 50.0 m/s straight up. The ball has a mass of 145 g and is in contact with the bat for 1.80 ms. What is the average vector force the ball exerts on the bat during their interaction? Now, I know how to draw the diagram to visualize the approach, I know that ρ = m * v, and I know that force = Δp/Δt. When I get my final answer, the components of the average force are (-3786i + 4028j)N. However, the answer has the signs reversed. Why is that the case? Thanks in advance for the help!