If they align the object at the very edge of the ruler, the measurement in inaccurate. They would have to start the measurement at 0 to get an accurate measurement. When starting at the very edge, you are not taking into account the little bit of the ruler and it between the edge of the ruler and the 0 marker.
Some people start at the 1 cm mark (and then subtract 1 from their raw measurement) to make sure they have the most accurate measurement they can get.
I'm pretty sure that is what you are talking about. Hope this helps!!
Answer:
i think it is car B because the greater the speed, the greater the drag force acting on the vehicle
Explanation:
The projectile has a height <em>h</em> at time <em>t</em> given by
<em>h</em> = (14.0 m/s) <em>t</em> - 1/2 <em>g t</em> ²
where <em>g</em> = 9.80 m/s² is the magnitude of the acceleration due to gravity. Solve for <em>t</em> when <em>h</em> = 0 :
0 = (14.0 m/s) <em>t</em> - 1/2 <em>g t</em> ²
0 = 1/2 <em>t</em> (28.0 m/s - <em>g t</em> )
1/2 <em>t</em> = 0 <u>or</u> 28.0 m/s - <em>g</em> <em>t</em> = 0
The first equation says <em>t</em> = 0, which refers to the moment the gun is first fired, so we ignore that solution. We're left with
28.0 m/s - <em>g t</em> = 0
<em>t</em> = (28.0 m/s) / <em>g</em>
<em>t</em> = (28.0 m/s) / (9.80 m/s²)
<em>t</em> ≈ 2.86 s
The correct answer would be A) Auroas
Hope this helps ya!
