Science Buddies: "Ask an Expert"

I have to do a science project on how angle affects the distance of a throw, but i'm stuck on the research part and cant find good answers anywhere. For now, I need a good definition for launch angle and how to measure launch angle. Could you please help? Although i'm only 11, I'm in 7th grade.
thanks

Hello aggron2000,

When launching a projectile (ball, brick, book, etc.) the "launch angle" is usually defined as the angle between the horizontal and the direction in which the projectile is released. So if you throw a ball exactly horizontally, it would have a launch angle of zero. If you throw it exactly straight up it would have a launch angle of 90 degrees.
It's hard to throw with your arm at a fixed angle, hard to measure the launch angle, and hard to throw always with the same launch speed. To get around these problems, you can use a mechanical launcher. Search Science Buddies for terms like "launch angle," "launcher," "trajectory," or any phrase that seems related to what you need to know. I searched for "launch angle" and found https://www.sciencebuddies.org/science- ... p061.shtml. You might not follow the launcher plans there exactly, but the description should give you some good ideas.
Please get back to us with any specific questions.
Good luck.

Hello aggron2000,

You got some good advice and ideas from wendellwiggins, and I can expand on that a bit.

Besides the approach used in the ScienceBuddies experiment Wendell cited, there are a number of projects in the ScienceBuddies system dealing with catapults. These are machines from ancient history used in battles to "throw" things at the enemy. They are great ways to study things like throwing angle. Just go to the ScienceBuddies Project Guide and search for "catapult". You'll see several project ideas. A broader search using Google will turn up lots and lots of catapult experiment ideas.

If you would really like to study the process of throwing with your arm, there are ways that are not too difficult to make the measurements you need. One way is to video record someone throwing an object. You could then play back the video in stop action frames and make the measurements of angle you would need.

Whatever you do, be sure to have fun!