Projectile Motion

All blocks today worked with projectile motion - some blocks working with horizontal projectiles and others with projectiles launched at angle. B and C blocks worked with projectiles launched at an angle, building on the techniques they practiced with horizontally-launched projectiles. We lose the ability to set the initial velocity in the y-direction to 0 m/s, which complicates matters, but if you work thoughtfully and in a stepwise fashion, the problems are manageable. Break the initial velocity into it's x-and y-components, remember that v_x is constant and the y-velocity at the top of the rise is 0 m/s and that if you launch and land at the same point, you have a symmetrical parabola. That last piece can be of great help, since sometimes it is easy to work with one half of the parabola, rather than the whole thing, and just multiply your values by two. Solve for time to top of rise and multiply by two to get the entire time in the air, for instance. On Monday, we will look over these some more and get more practice, if necessary.

E Block worked on the Projectile Motion lab, which verified the assumptions and calculations we worked on with our practice problems. As long as you know height, you can calculate how long it takes the projectile to hit the ground. With time and and a known, constant horizontal velocity, predicting horizontal displacement is quick and easy. We'll go over this lab on Monday and then start on projectiles launched at an angle.

F Block had their horizontal projectile lecture, which helped to clarify and explain observations made in yesterday's lab. Yes, the velocity in the x-direction is constant. Yes, the acceleration in the y-direction is the standard velocity for gravity. Yes, you can analyze each component of the motion separately, for they are independent. Use the skills you practice in lab and the example problem we worked on the board to tackle the homework problems this weekend. On Monday, we'll go over them and then start with projectiles launched at an angle.

Have a good weekend!