Activity 4: Predict the time for a steel sphere to roll down an incline. Steel Sphere Acrylic Sphere A Length of Track (cm) (s) 80 cm 80 cm (Step 1, use 80 cm) B Angle of Elevation (0) in Degrees (Step 1) C Calculated Time from s=0 to s=80 (formula from step 2) D Measured Time from s=0 to s=80 (step 3 with stopwatch) E % Difference (step 4) first value - second value percent difference = first value + second value x 100% Question for Activity 4: What effect does the type of the sphere have on the time of the object to travel the measured distance, explain