I'm creating a pneumatic launching device to shoot projectiles vertically. I guess the closest thing to compare it to would be a regular gun. Once it leaves the barrel, it will be in a constant state of deceleration until it reaches its peak (no additional thrust provided).(adsbygoogle = window.adsbygoogle || []).push({});

Ignoring frictional losses, is there a systematic way to calculate the projectiles rate of deceleration? Does the weight matter (i.e. will a tennis ball and a bowling ball decelerate at the same rate)? Does the exit speed matter?

Ideally I would like to take a projectile, knowing the force provided by the pneumatic actuator and the weight of the projectile, calculate exactly how high the projectile will go. Then once I've mastered calculating it in a frictionless environment, put it in a wind tunnel and calculate losses due to friction.

Also, just a general question somewhat related, in an environment with friction, will it take the exact same amount of time to reach ground-to-peak as peak-to-ground?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Gravity's opposition to accleration

**Physics Forums | Science Articles, Homework Help, Discussion**