Motor Daddy
Valued Senior Member
You can, assuming the "air" is moving in the direction of travel.
If the wind is in the direction of travel, the wind pushes the vehicle forward. (F-wind = m*a). This is simply the wind pushing against the structure of the car.
The tyre movement rotates the propeller (note that it is not the wind which rotates the propeller, but the motion of the tyres), which pushes air back, generating additional force (F-prop) causing the car to accelerate even more (F-net = F-wind + F-prop).
Eventually the car will travel faster than the wind - e.g. if wind is 20 mph then the vehicle can go much faster than that in the direction of wind, before the drag of the vehicle, and friction, balances the forward forces. (F-net = F-wind + F-prop + F-drag + F-friction = 0).
No motor, just wind power.
Obviously if the wind then drops, the drag will gradually slow the vehicle down.
I thought it explained it all in the video you linked in the OP, although it has been a while since I saw that one.
Did you even read my opening post? Did you go to time 14:45 in the video and understand what I am talking about?
Do you understand I am talking about the craft and the treadmill (that's plugged into the outlet?)
1. Tell me how you measure the speed of the belt BEFORE you put the craft on it? Where is the power coming from?
2. Tell me how you measure the speed of the craft?
3. Which speed is faster? Which ft/sec is greater?
4. Billvon started the conversation of power, because sometimes he gets power and speed mixed up. The title of this thread is "Faster or Slower?" The title of this thread is NOT "More power or less power?"
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