Acceleration with inclined ramp (Frictionless)

AI Thread Summary
The acceleration of a skateboard down a frictionless ramp inclined at 19.5 degrees is calculated using the formula g sin(theta), resulting in an acceleration of 3.271 m/s². The confusion arises from the misconception that the formula should be g divided by sin(theta), which would incorrectly suggest an acceleration greater than the gravitational constant of 9.81 m/s². The correct understanding is that g sin(theta) represents the gravitational force component acting along the incline. Visual aids, such as diagrams, can clarify this concept further. Overall, understanding the correct application of the formula is essential for accurate calculations in physics.
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1. What is the acceleration of a skateboard down a ramp inclined at 19.5 degrees to the horizontal?

3.271 is the answer.




2. I know g Sin\vartheta is the equation to get it, but I don't get why it isn't g divided by Sin\vartheta



3. In my head I thought the picture was like this:
2wew8bq.jpg


I know this should be something super easy, so please explain. haha
 
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g sin theta gives you the component of the acceleration of gravity along the incline.
g/sin theta would give you a number larger than 9.81m/s^2 which would make absolutely no sense.
 
hp-p00nst3r said:
g sin theta gives you the component of the acceleration of gravity along the incline.
g/sin theta would give you a number larger than 9.81m/s^2 which would make absolutely no sense.

Right, but the first statement still confuses me. Is there a picture you could go by for this?
 
This should help you

http://img145.imageshack.us/img145/6905/accelerationvectorgh9.jpg
 
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Okay, that totally makes sense now. Thanks! :)
 
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