The purpose of this lab was to have students use the horizontal projectile
motion equations in order to calculate the velocity of a marble rolled off a
table. A cardboard ramp or rubber band was used to give the marble initial
velocity. Students did three trials at two different speeds. The
distance the marble traveled (x), the time in the air (t), and the height of the
table (y) were measured and recorded. These were the experimental
values. The accepted value for time was calculated using y = 1/2gt2 and
percent error for time was calculated. The velocity of the marble was
calculated using x = vt. The experimental and accepted values of t were
plugged into the equation and percent error for velocity was calculated.