This is a fun and exciting project we did in my Physics class. We had to try several times to finall get it, but we had a fun time. Its an easy lab if you do it right, and you dont need to buy to many things. You can race your friends, or do this as an experiment.
What you will nead is...
1 Hot wheel car
1 model rocket engine of your choice
For the track.
1 long plank of wood
2 L brackets
1 spool of 12 gage alluminum wire
Step 1: Choosing a Car
Get a hot wheel car. Make sure when you push it, it goes in a straight line. Your going to want a car that has some space off the ground so you have room for a zip tie, or tape.
We found that the cars that worked the best, rolled straight, and had lots of room off the ground. The weight of the car is important as well. To much weight can cause displacement for your car.
Step 2: Choosing a Rocket Engine
Now what you need to do is choose a rocket engine. From my experience, C is extremely powerful. A or B should be a sufficient engine, but if you want to be crazy, or if your slightly retarded, you can use a D or E.
The higher powered rocket, the more acceleration and speed. When we ran the tests we saw an average speed from 20 to 40 meters per second. These were all just using C engines, so you can imagine what a higher powered engine will do.
Step 3: Getting a Tube
You need 2 thin tubes, like a pen cap, a straw, or something similair to attach to your car so you can run the wires through it and so the car stays on the track.
I suggest to stay away from straws, we found that the force of the rocket causes the wire to slice the straw open.
Step 4: Attaching Car, Engine and Tube
There are lots of different ways to attach the rocket and tubes to your car. We found that if you use electrical tape, and then reinforce it with hot glue and a zip tie, everything usually stays together.
Hot glue alone will not work. The engine will melt the glue and it will fly off. It happened to us several times.
Dont use just a zip tie, the acceleration from the rocket will cause the engine to fly out, no matter how tight you think it is attached.
The best method is to use more than one of the methods, or preferably all three.
Note!!! Friction is a major player when launching your cars! Keep that in mind when putting everything together.
Step 5: Finishing Car
Now that our car is all asembled and ready, theres just one more step to make it worthy. Put the fuse and butt plug into the rocket, and your car is done! Now on to the track.
Step 6: Constructing Track
How you build your track is up to you, but your going to want a long plank of wood, width is up to you. Place two L brackets at each of the track. Drill them into place. The Next step is getting wire. I highly recomend steel wire, or 12 gage alluminum because its strong, and it will keep your car on the track. Feed the wire throught the L brackets, feed through the car and then secure the wire on the other L bracket. Make sure the wire is nice and taught so that the car wont fly off.
I suggest using two wires. This will make sure the car goes straight, and it has less chance of the car flying off. We were only able to succesfully collect data after we used two wires.
Step 7: Congradulations!
Now your ready to race your car! All you need is a battery and wire to launch your car, and then you can race away!!!