In this video, a 0.003 kilogram ball rolls on an inclined track with a constant slope that is about 0.32 meters long and then rolls on a flat track that is about 0.68 meters long. The ball starts at the top of the incline at rest and rolls for about 3.55 seconds before being hit by a plank, causing it to roll in the opposite direction. The force with which the plank hit the ball can be calculated with the formula ((m((xpost-force final-xpost-force initial)/(tpost-force final-tpost-force initial)))+(m((xpre-force final-xpre-force initial)/(tpre-force final-tpre-force initial))))/(tforce final-tforce initial), with m representing the ball’s mass, x representing the ball’s position, and t representing the time at the ball’s corresponding position.
OBSERVATIONS
The following images show positions and times of the ball during the experiment.
m=0.003 kilograms, xpre-force initial=0.95 meters, tpre-force initial=3.27 seconds |
xpre-force final=1.00 meters, tpre-force final=3.55 seconds |
tforce initial=3.55 seconds |
tforce final=3.60 seconds |
xpost-force initial=1.00 meters, tpost-force initial=3.55 seconds |
xpost-force final=0.95 meters, and tpost-force final=3.60 seconds |
As observed, the force with which the plank hit the ball is -0.049 Newtons.
REFLECTIONS
I expected this because the force was to the left and it resulted in a greater velocity than the velocity before the force.
NOTE
The ball never travels at a constant velocity due to friction and air resistance, so the closest possible measurable two positions before and after the force were used to estimate the instantaneous velocity of the ball at these moments.