1. The problem statement, all variables and given/known data This was actually a lab for class today. Basically, a marble rolls down a 2.26m slope, in 3.12s. Find the angle of the slope. Assume there is no friction. 2. Relevant equations v=d/t a=v t a=g sin (theta) 3. The attempt at a solution v=2.26/3.12 = 0.724m/s since that is Avg. V, multiply by 2 to get Total V. V=1.45m/s a=1.45/3.12=0.464m/s2 so with that, i change the equation with the angle to solve for theta, getting Invsin (a/g) = theta Invsin (0.464/9.81) = theta theta = 2.71 This seems good on paper, but in the lab, this is to find the angle of a slope outside. The actual slope is steeper than 3 degrees, it's probably about 10-20 degrees. So is there a problem with my calculations? Or are there sources of error that cause the angle to come out as so small?