Liftoff! IB Physics Students Launch Rockets

We have liftoff!
Justin King’s IB Physics students launched water bottle rockets in a field adjacent to the high school on Wednesday.
From a safe distance away from the launch site, the students pumped air into inverted two-liter soda bottles that had partially been filled with water.
The bottles were filled with air to roughly double the pressure inside a fully inflated car tire.
Then, after 3-2-1 countdowns, the students triggered liftoff of their rockets by releasing clamps that had kept the rockets on the ground.
As the rockets rose, a trail of water spewed out of the airborne bottles.
Classmates measured the height achieved by the rockets using trigonometry skills.
The students responsible for calculating the rocket’s height each had a protractor and stood a prescribed distance from the launch site. And by recording the angle relative to the ground when the rocket was at its apex, the students could calculate the precise height the rocket achieved.
The students had built their rockets as part of their final project.