Final answer:
The displacement over time graph for the soccer ball being kicked back and forth would show a parabolic shape, similar to projectile motion as seen with a hockey puck. The shape is due to the ball's travel from the player to the goalie and back again. Additionally, a goalkeeper could potentially score from a goal kick directly into the opposite goal with sufficient speed and correct conditions.
Step-by-step explanation:
The scenario described involves a defensive player kicking a soccer ball 20 meters back to her goalie. When the goalie sends it back, we want to draw a rough sketch of the displacement over time graph, without knowing the exact timings. To visualize this, imagine a displacement-time graph where the horizontal axis represents time and the vertical axis represents displacement from the starting point.
Initially, the ball travels 20 meters towards the goalie, reaching zero velocity when it stops. Then, it travels back the same distance when the goalie returns it. The graph will start at zero, rise to 20 meters, return to zero, before rising again as the ball is kicked back. This displacement over time graph resembles the parabolic arc you would expect from a projectile motion, similar to that of a hockey puck being shot towards a goal in ice hockey, as seen in question 46.
Regarding the goalkeeper taking a goal kick and potentially scoring a goal across the field, as per question 43, it's theoretically possible given the kick speed (30 m/s) and the distance (95 m), depending on factors like air resistance, ball trajectory, and the goalkeeper's skill.