3.Acceleration of Gravity on an Inclined Plane

The purpose of these lab is to find the acceleration of gravity by studying  the motion of cart on an incline plan.                                                                                                                                         


We set up the track putting the wood friction block under the track support at approximately 50cm raising the end of the track.

To determine the inclination of anlge X we solve a for the triangle.

Since the force of friction acts with the force of gravity when the cart is going up the track and against the force of gravity when the cart is going down the track, we can average the slightly increased acceleration (when going up) with the slightly decreased acceleration (when going down) to obtain an acceleration that depends only on the force of gravity. If we call g the acceleration along the track is g sin θ  where theta is the angle of incline for the track.


g sin θ= (a1+a2)/2

a 1	a 2	g
-0.3316	0.2679	9.83232

There were 3 trials for the first angle 

 

 

For the second angle there were three trials as well.

 

 

 

 





Conclusion:
According to two experiments, we found when θ is larger, our experimental data are closer to actual data(0.5% diff compare to 8.2% diff). The reason is that when θ is larger, the motion of cart is closer to free fall, which is influenced less by the disturbance. The causes of error:  Air resistance also against the motion, Our table is not horizontal, so our θ is not precise enough and the error of the equipment and the error when we read the data.

In this lab, we learned acceleration along the track is gsinθ where θ is the angle of inline for the track. we can use this property to estimate the gravity. We also learned how to control the variable to get another group of data, then try to think abut what cause the difference.



a 1

a 2

g 

-0.3316

0.2679

9.83232