A model rocket rises with constant acceleration to a height of 4.0 m, at which point its speed is 25.0 m/s.(adsbygoogle = window.adsbygoogle || []).push({});

How long does it take for the rocket to reach this height? Ans: t= 0.32s

What was the magnitude of the rockets acceleration? Ans a= 78 m/s^2

"Find the height of the rocket 0.20 seconds after launch."

I cant seem to get it right, I know its at least close to 1.5, because that was my original answer but the darned online system says "Not quite. Check through your calculations; you may have made a rounding error or used the wrong number of significant figures." the answer is supposed to be to two significant figures.

"Find the speed of the rocket 0.20 seconds after launch."

I havent attempted this part of the question yet because I think I need to use what I figure out from the previous question to work on this.

All this stuff is not hard, but I cant seem to grasp the simple concepts that Im missing in figuring it out, any help and/or guidance would be really appreciated.

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# Homework Help: Model Rocket question regarding height,time,acceleration

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