Video Analysis of an object projected horizontally

Vertical and horizontal velocity of an object projected horizontally(by Sheldon Chen).

Other videos by St-Mary's High School

Shoot-n-Drop

An apparatus that at once shoots a billiard ball horizontally and drops another one vertically from an equal height. Even though the two have different initial velocities, they both accelerate in the same direction and at the same rate due to Earth's gravity--this is confirmed by seeing and hearing both balls land simultaneously.

While we did our best to make sure the setup is level and the apparatus is precise, the video shows the balls actually land about 0.02 s apart from each other (the slow-motion part was done in 60 fps, and there seems to be a difference of about 1 frame). We consider this difference to be negligibly small. Normally the apparatus is positioned about 2 meters above the floor, and the difference in landing time is just as imperceptible. You will notice the "drop-ball" bounces towards the center of the picture. We think this is mostly because the concrete floor has small pockmarks and other local irregularities, which on average combine to form a level surface but individually can cause funny bounces. The ball may also have a very small horizontal velocity due to the way in which it is dropped.

Other Harvard demonstrations

Center of Mass Trajectory

Odd-shaped objects with their centers of mass marked by orange paint are thrown. While the objects appear to follow very wobbly trajectories when viewed under bright lights, under black lights you can see that their centers of mass travel in smooth parabolas.

Source:  MIT TechTV

See other MIT physics demos

Weightless dog in a plane

The plane follows a parabolic path, simulating zero gravity.

2-D trajectory of a basketball

Basketball jump shot.

2-D trajectory of a soccer ball

Soccer ball dropped.

Projectile Motion, velocity vector

Velocity vector and components during projectile motion.

Stuntman (Big slip)

A spectacular application of conservation of energy and motion of a projectile.