Kinematics Question on falling rock

AI Thread Summary
The discussion revolves around a kinematics problem involving a rock thrown upward from a 30m cliff. The initial calculation mistakenly adds the height of the upward motion (10m) to the cliff height (30m), resulting in a total of 40m. However, the correct approach focuses on displacement, which measures the distance from the initial position to the final position, leading to a displacement of 30m. The importance of understanding displacement versus total distance traveled is emphasized, clarifying that the rock's path does not affect the displacement calculation. Ultimately, the correct answer to the problem is 30m, highlighting the need for precise interpretation of kinematic concepts.
Riju
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Homework Statement


A rock is thrown straight upward from the edge of a 30m cliff, rising 10m, then falling all the way down the base of the cliff.

Homework Equations

The Attempt at a Solution


Well, because the rock was thrown 10m up, and then it came all the way down, I added those quantities (10m+30m) so I got 40m. But since the displacement is the object's initial position to its final position, regardless of the path actually taken, would I have to count the rock before it was thrown? Then the answer would be 30m
 
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Riju said:

Homework Statement


A rock is thrown straight upward from the edge of a 30m cliff, rising 10m, then falling all the way down the base of the cliff.

Homework Equations

The Attempt at a Solution


Well, because the rock was thrown 10m up, and then it came all the way down, I added those quantities (10m+30m) so I got 40m. But since the displacement is the object's initial position to its final position, regardless of the path actually taken, would I have to count the rock before it was thrown? Then the answer would be 30m[/B]
You haven't stated what question you are asked.
 

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