Hopefully once I hit it it keeps moving so I can get a home run.
Oh no, He hit it! Now someone needs to catch it in order for it to come to a rest
The pitcher throws the ball. The force called air resistance causes the ball to start slowing down. Newtons second law states than an object in motion stays in motion and an object at rest stays at rest unless acted upon by an outside force.
When the batter hits the ball the batter is applying a different amount of force to the ball which is going to cause the ball to accelerate away from the batter. The batter is hoping that the ball is going to accelerate enough that he can get a home run.
Newtons Second Law
Once the ball is accelerating away from the pitcher and batter the pitcher is hoping that someone catches or that the ball hits something so then the ball will come to a rest.
These 2 people are playing tennis. Newtons second law states that f=ma which means that the more force that is applied the more acceleration there will be.
Since there was not a lot of force applied the ball wasn't able to make it over the fence since it didn't accelerate fast enough.
Once she added more force the ball was able to accelerate faster and make it over the fence which helped her win the point.