Spring launch of slide on inclined plane

We use this result to analyze an additional simple experiment on the air-track. This time we launch a slide up the track with an incline. The question we wish to answer is how high up the track will the slide get?

Since this question does not involve time our energy flag should pop up: It is to our advantage to use the Work-Kinetic energy theorem. We choose:

Initial State:

Brick at rest spring compressed to

Final State:

Brick momentarily at rest a distance, L above the point of release

We write the Work Kinetic energy theorem:

The work done by the spring is

while the work done by gravity is

where is the angle of inclination. Taking into account that there is no kinetic energy in the initial or final states and using we obtain

Putting in numbers we get

We do the experiment and find excellent agreement with the calculation.