Projectile Motion Equations: Checking Answers for Moving Objects

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The discussion focuses on identifying which moving objects adhere to the equations of projectile motion. It confirms that a stone thrown underwater, a ball thrown in any direction, a jet airplane in flight, and a rocket after engine failure all follow these equations. However, a rocket leaving the launch pad does not qualify as it is influenced by thrust, which introduces additional forces. The key takeaway is that ideal projectile motion involves only one acting force, gravity, which must be considered when evaluating the scenarios. Understanding these principles is crucial for accurately applying projectile motion equations.
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Could anyone please double check my answers to each of the following statements. Thanks

Homework Statement



Determine which of the following moving objects obey the equations of projectile motion.

True A stone is thrown under water.
True A ball is thrown in an arbitrary direction.
True A jet airplane crosses the sky with its engines thrusting the plane forward.
True A rocket moves through the sky after its engines have failed.
False A rocket leaves the launch pad.
 
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Melchior25 said:
Could anyone please double check my answers to each of the following statements. Thanks

Homework Statement



Determine which of the following moving objects obey the equations of projectile motion.

True A stone is thrown under water.
True A ball is thrown in an arbitrary direction.
True A jet airplane crosses the sky with its engines thrusting the plane forward.
True A rocket moves through the sky after its engines have failed.
False A rocket leaves the launch pad.
Not all your answers are correct, even when air resistance is neglected (which should have been stated in the problem). Hint: There is only one force acting on an object in ideal projectile motion problems. What is that force? How does it affect your answers?
 

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