Free Fall Lab Natalie Soria Lab Partners: Ryan Michaely Iqra Haji Yan Huang 1. Purpose: The purpose of this experiment is to determine the acceleration due to gravity by observing the motion of a free falling object. 2. Equipment Used: A. Timer Switch B. Time-of-Flight Accessory C. Control Box D. AC adapter E. Drop Box F. Steel ball G. Solid gold ball H. Big plastic ball 3. Method Used: 1) Place the steel ball on the drop box. 2) Set the timer to “Time: Two Gates” mode. 3) Measure the distance between the bottom of the ball and the plate and record in table 4) Release the ball using the timer switch and record the time it takes to fall. ) Change the distance and repeat step (4) until table is complete 6) Repeat steps (3) – (5) with solid golf ball 7) Repeat steps (3) – (5) with big plastic ball 4. Diagram: Time-Of-Flight Accessory Time-Of-Flight Accessory Timer Switch Timer Switch Timer Timer DROPBOX DROPBOX 5. Data: STEEL BALL Table 1: Determining the acceleration of the steel ball dropped Distance (M)| Time(S)| Time(S2)| 0. 80m| 0. 4074s| 0. 166s2| 0. 75m| 0. 3969s| 0. 1575s2| 0. 70m| 0. 3809s| 0. 1451s2| 0. 65m| 0. 3692s| 0. 1363s2| 0. 60m| 0. 3546s| 0. 1257s2| 0. 55m| 0. 3438s| 0. 1182s2| SOLID GOLF BALL

Table 2: Determining the acceleration of the solid golf ball dropped Distance (M)| Time(S)| Time(S2)| 0. 80m| 0. 4044s| 0. 1635s2| 0. 75m| 0. 3906s| 0. 1526s2| 0. 70m| 0. 3785s| 0. 1433s2| 0. 65m| 0. 3643s| 0. 1363s2| 0. 60m| 0. 3494s| 0. 1257s2| 0. 55m| 0. 3390s| 0. 1182s2| PLASTIC BALL Table 3: Determining the acceleration of the plastic ball dropped Distance (M)| Time(S)| Time(S2)| 0. 80m| 0. 4111s| 0. 169s2| 0. 75m| 0. 4026s| 0. 1621s2| 0. 70m| 0. 3849s| 0. 1481s2| 0. 65m| 0. 3698s| 0. 1368s2| 0. 60m| 0. 3553s| 0. 1262s2| 0. 55m| 0. 3382s| 0. 1144s2| 6. Calculations: Determining Avg. Time for each trial

With formulas:With numbers: T1+T2+T3 = Avg. T (S)(. 4072s) + (. 4078s) + (. 4073s) = Avg. T(S) 33 .4074s = Avg. T (S) Determining T2 With formulas:With numbers: T = S2 T = (0. 4111s)2 T = 0. 169s2 7. Conclusions: The objective was to determine acceleration due to the effects of gravity. Gravity stayed constant through the whole experiment. Source of error could be due to measuring between ball and mat inaccurately. Answers to questions (1) Using our kinematics equations and the concept of a straight line (y=mx+b), show that the graphs made in part (7) should indeed be a straight line.

What should the theoretical values for the slope and y-intercept be for this graph? (2) What are the actual values of the slope and y-intercept for the three graphs. Compare these to the theoretical values. Calculate the gravitational acceleration for all three balls from this information. (3) Comment on why the acceleration due to gravity is less for the plastic ball than the others. Give some ideas why you think this particular ball would behave like this and the other balls would not. The gravitational acceleration due to gravity is the same for every object, the total acceleration is not.

Acceleration is reduced a bit by the particular mass of the ball. In cases where “m” is large (like the steel ball and golf ball), the factor will be small and therefore falling at almost the same acceleration. But in the case where “m” is small (like the plastic hallow ball) the factor could be large, and therefore the balls acceleration could be significantly less due to the hollowness of the ball. Although the plastic ball is bigger in size, its mass is lighter. (4) A ball is thrown upward. While the ball is in the air, does its acceleration increase, decrease, or remain the same?

Describe what happens to the velocity of the object from when it is thrown until when it returns. While in the air, the balls acceleration would remain the same. When the ball is thrown, its velocity is positive and decreasing as it’s going up, and at the highest point, the velocity is zero. When it’s coming back down, the velocity is negative and increasing. (5) Explain conceptually (without using equations) what the shape of Distance vs. Time would look like for a ball falling to the ground. Use kinematics to explain why it would be like this. The falling ball is moving at a constant rate ( 9. 80 ms-2 )