Pros and Cons design 3

Design 3
Pros

• simple design 
• easy to make 
• retestable 
• uses newtons 3rd law
• a lot of potential energy in rubber bands 
• slingshot design used in toys 
• upgrades easy to make 
• car is light and moveable 
• travels in a straight line 

Cons 

• can spin of course
• rubber bands can break 
• takes a lot of attention to detail to load 
• sponges car may bend when being loaded 
• shoot has to be reinforced to make sturdy