Which of the following is an example of projectile motion?

a jet lifting off a runway

a thrown baseball

an aluminum can dropped straight down into the recycling bin

a space shuttle being launched

I think it's b, but I'm not sure.

You're on the right track! Projectile motion refers to the motion of an object that is launched into the air and moves along a curved path due to the influence of gravity. It has both a horizontal component and a vertical component.

Out of the given options, a thrown baseball fits the description of projectile motion. When a baseball is thrown, it moves in a curved path as it ascends into the air and then descends back down due to the force of gravity acting upon it. Therefore, the correct answer is option b, a thrown baseball.