Question

best idea for physics model

Answer 1

If you have to give only presentation in ur school than u can simply make a chart and with the help of double tape paste it on your school black board....... It can be easily removed...... But if it is ur homework.... Than u can make use of 4 equal size cardboard or shoe box and colored paper acc. To ur project..... U can also use wires if you wants to show flow of current.......... And all

Answer 2

Why not you try to make a rollercoaster . 
i'm going to tell you which stuff do you need . 

some marbels or you can take ball bearing ,tubes , Tape Poster board ,Glue ,Books ,Metal empty boxes,  Clay , Cups ,  Foam insulation tubes ,  Wood blocks  ,Cardboard tubes  etc which can use .
 
Method :

1. Spherical objects such as marbles and ball bearings make the best "cars" for your roller coaster.
2 . If you use poster board or boxes, cut out long strips to make your track.
build your track so that the cars can run smoothly on it
3. Use the adhesives to connect track pieces together . 
4. Remember the laws and forces of motion when building your roller coaster track. Your first hill must be the tallest to build up enough potential energy to get your car through the track. Adjust hills and loops so that the car will have enough velocity to make it through the course without having so much speed that it flies off.

principle it works in of centripetal force that the rollercoaster ride not fall during doing loops  .

hope it helps you my friend 
_____________________________________________________________