?!
CHECK IT OUT
— You may have experienced the power supply of car models in your daily life. If you inflate a balloon and leave hold of, the balloon will fly around the room. Because of the air pressure inside the inflatable balloon is more than the outside air pressure, and this phenomenon is caused by trying to balance the pressure difference between inside and outside. As long as you close the opening of the balloon, the internal air will press against the elastic outer wall. Once you leave hold of the balloon, the air will flow out of the balloon at a very high speed. The same thing happens to your car. ?
What H a p p e ne d There?
But Why Do
or
Wh
W ha t' s th e Us e of
Wa ter?
a car with — If you try to drive ly and don't use compressed air on car can't move. water, you will find and reac tion force Because of the force pend on the mass in the experiment de yed by the nozzle. of the material spra ty of water is much And since the quali ality, the force that higher than air's qu rd is also greater. drives the car for wa
Ti p You can find more information about "Reflection in Nature and Technology" on page 15.
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a l l o o n s F en
ly
B
riv D yC e a n Yo u r C a r B Reaction Force Balloon rise
Force air Outflow
BALANCE = Balance of power
— The discharged air will produce a reaction force of the same magnitude, and the reaction force is opposite to the direction in which the air is discharged. Therefore, when air is discharged from the back of the balloon, the balloon will accelerate in the opposite direction.
