Frames of reference, trajectory

AI Thread Summary
The discussion centers on comparing the trajectory of a ball thrown in a headwind versus one thrown from a moving platform, like a boat. It emphasizes that physics remains consistent across different inertial frames, suggesting that analyzing both scenarios from an observer's perspective on the bank can clarify the differences. The static throw involves a wind speed of 20 m/s against a vertical throw of 30 m/s, while the boat moves at 20 m/s in still air with the same throw. The key point is that the perceived trajectory will differ based on the reference frame of the observer. Understanding these dynamics is crucial for accurately interpreting the effects of wind and motion on projectile motion.
James9118
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I'm hoping you can help with a debate I'm having with a friend regarding whether throwing a ball in a headwind is the same or different from throwing a ball from a moving platform (lets say an open boat).

If you want some numbers, could you please work with these:

For the static throw, can we imagine the wind is blowing at 20m/s and the throw is made at 30m/s vertically. Cd of ball = 0.5, mass of ball = 0.1kg, diam of ball = 0.1m.

For the boat, this is traveling at 20m/s in still air. Same throw, same ball.

So is the trajectory, as viewed by the thrower in each case, different or the same?

Many thanks, James
 
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Physics is the same in all inertial frames. You just have to find appropriate inertial frames to apply this concept.
 
Welcome to PF;
What mfb said...
Since the object is to be convincing as well as correct, I'd do both cases from the POV of someone standing on the bank and then translate to the throwers POV.
That should help.
 
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