Cart with hanging mass

 

Predicted vs. Measured Velocity

The predicted velocity is calculated using the formula shown and the measured velocity is from video analysis. The velocity predicted is considerably lower than the measured velocity. This could be due to experimental error.

Velocity Predicted: 0.416 m/s
Velocity Measured: 0.743 m/s +- 0.064

Dependencies of Launch Velocity

The launch velocity changes drastically when masses are changed. The two graphs show the velocity and position change of the cart when the cart weight is added and when the mass of the hanging object increases. When the distance the object drops is lower, the velocity of the cart decreases as well. 

Mass added to cart (+500 g)

velocity = 0.381 m/s +- 0.03

Mass of hanging object (350 g) velocity = 1.927 +- 0.142

Force analysis on weight vs. tension and force from string on cart

The strings tension only equals the hanging mass's weight when the system is at rest or moving at a constant velocity. The tensions effect on the cart is not always equal to the hanging mass's weight because the acceleration and friction modify the tension on the cart.

Frictional Force

The frictional force was not the same if the string exerted a force on it. At equilibrium, the static friction is ensuring it does not move and once it feels the force of tension from the string, the friction changes into kinetic friction. This does agree with my initial prediction.