2º EM - Laboratory: Horizontal Launch

 One of the great branches of Physics, studied since the beginning of human history, is the movement of projectiles called Ballistics. They involve projectile launch in 3 situations: when the launch is made in the vertical direction (the velocity only has a vertical component), when the initial velocity has only a horizontal component and when the initial velocity has both vertical and horizontal components (called oblique launch). In today's class we will work with horizontal releases. To do this, go to the link below:

https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_pt_BR.html

1. After accessing the link, enter the second icon: vectors. Click on the " + " sign at the base of the cannon and raise it until it reaches 15 m and place the cannon horizontally (0° inclination). Select a 0.2 m diameter, 2 kg mass cannonball, turn off air resistance, select a velocity of 10 ms-1 and fire the cannon (red icon at the bottom). Measure horizontal range and movement time. Repeat the procedure for speeds of 15 m/s and 18 m/s.

Questions:

Has the horizontal range changed?

Has the movement time changed?

Has the vertical component of velocity changed?

CONCLUSIONS:

2. Change the height to 12 m, launch with speeds of 10 m/s, 15 m/s and 18 m/s. Measure horizontal range and movement time. Compare with previous results and draw conclusions.

3. a Return the cannon to a height of 15 m, quadruple the bullet diameter and repeat the procedure for a velocity of 18 m/s. Comparing the two situations, was there any change in movement time? And in the horizontal range?

3. b Return the diameter to 0.2 m and quadruple the bullet's mass. Repeat the procedure for the speed of 18 m/s. Comparing the results for this situation and the initial one, was there a change in the movement time? And in the horizontal range?

CONCLUSIONS:

4. Go back to the starting bullet (0.2 m and 2 kg) but now add air resistance.

a. Make throws at 5 m/s, 10 m/s and 15 m/s, noting movement time and horizontal reach.

b. Triple the bullet diameter and repeat this procedure.

c. Return to 0.2 m in diameter and triple the bullet's mass, repeating the procedure used in the two previous situations.

QUESTIONS:

Does fall time depend on launch speed?

Does the fall time depend on the diameter of the bullet?

Does the fall time depend on the bullet's mass?

CONCLUSIONS: