Is D=1/2*a*t^2 the Right Formula to Calculate Rocket Height?

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The formula D=1/2*a*t^2 can be used to calculate the height of a bottle rocket, but it's important to remember that the total time measured includes both ascent and descent. To find the maximum height, the total time should be divided by two, as the rocket takes half the time to reach its peak. The acceleration due to gravity is correctly noted as 9.81 m/s^2. Using the adjusted time in the formula will yield the correct height. This method effectively accounts for the parabolic trajectory of the rocket's flight.
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I need to find the height a rocket travels(bottle rocket). If I use this equation, ignoring air resistance, etc... I should use a stop watch from the time of launch till it hits the ground equaling t. a=9.81 m/s.


Is that the correct way to use the formula for this excerise?

Is there another way I should use it?

Is there another formula or method to find the height?, if so what?


--Thanks
 
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JEscribir said:
I need to find the height a rocket travels(bottle rocket). If I use this equation, ignoring air resistance, etc... I should use a stop watch from the time of launch till it hits the ground equaling t. a=9.81 m/s.


Is that the correct way to use the formula for this excerise?

Is there another way I should use it?

Is there another formula or method to find the height?, if so what?


--Thanks

It certainly isn't a bad way to do it. Just remember that it takes only half the time to get to max height as it does to get back to the ground.

BTW: I wouldn't be me if I didn't say something...I'm a real prig when it comes to units...The magnitude of a is 9.81 m/s^2, NOT m/s.

-Dan
 
Thank you for the unit correction, it is important( it was an embarrrasing mistake :frown: ). Let me review, the time( from launch till fall) I get should be divided by two to get the distance: so would I do d=1/2 *a*((t^2)/2) ?


thanks
 
Yes because the rocket travels in a parabolic shape. The overall time it takes includes both when it rises and falls and since you want the tallest height it flies, you want where time is at half of the overall duration in travel.
 
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