Defining net forces in problems using velocity vectors and wind vectors.

Mr. Olson Voyagers Science

CA 8th Grade Standard 2a: Students know when an object is subject to two or more forces at once, the result is the cumulative effect of all the forces.

In this game, you will be attempting to fly an airplane into a hurricane. You will need to adjust the wind vector with the velocity vector by adjusting magnitude and direction to fly the plane to its target.

First step, log on to the internet and enter the link below.

http://illuminations.nctm.org/ActivityDetail.aspx?ID=43 This link is also posted on the Voyagers Website

Your screen will look like this.

Here are the basic instructions, also available on the site.

Practice

Play with the simulation, experimenting with different combinations of length and direction, until you are familiar with how the game works. Turn off the sound if you find it disturbs others or yourself, and turn on the grid so you get a better picture of the mathematical relationship of the two forces.

You can grab the ends of the arrows and spin, stretch and shrink them, or you can use the slide bars below the game grid to adjust them.

After you (and your partners if playing in teams) have a good idea of how the simulation works, try to solve each of the problems on the next page with as few errors as possible. Give yourself 5 points for each successful turn. (Flying the plane into the storm.)

Challenge 1: Make the plane hover in one spot by balancing the force and direction arrows in opposite directions with equal magnitude. (See below)

Challenge 2: Make the plane drift backwards into the hurricane by turning its direction 180 degrees from the hurricane, and giving the wind a stronger magnitude than the planes forward motion. (Problem solve to do this one)

Challenge 3: Get the plane to drift into the hurricane using vectors that are at right angles with each other. (see below)


UNDERSTANDING THE NET FORCE CONCEPT

Challenge 4: Turn on the black arrow [show vector sum]. Drag the dot at the center of the arrow over the plane. Adjust the red and blue vector arrows with the slide bars until the black arrow (net force) [vector sum] is pointing at the target.

When you press [start plane] the plane should fly directly to the storm along the path of the black vector. (see below)

Challenge 5: Briefly explain from your observations of the three vector arrows and the behavior of the plane from the previous activity the interaction of the wind and velocity vectors and how they combine to form the vector sum.

Challenge 6: Repeat the exercises on the previous pages with the black vector sum arrow turned on to help you visualize what is going on.