no, the speedometer would show 10 and the car relative to the ground would be going 0.

 

How do you know when something's forward speed it matched? Because it will stop moving forward.

If I run 10mph, on a 10mph treadmill, then its matching my forward speed because I am not gaining ground.

If a plane is moving forward 10mph, and the treadmill is moving 10 mph backward...but the plane is still gaining ground...then is the treadmill still matching it's forward speed?

:thinking:

 

youre just confusing yourself more.

it is forward matched., but the conveyor belt has no effect on the plane... and it takes off!!

 

Nope, the cars speed is 10mph, so the speedo shows 20.

miles per hour. If it shows 10, it's not going any miles per hr. lol

 

when you're running on a treadmill, every time your foot hits the treadmill, it's pulling you back at 10mph. if you were wearing rollerblades instead, the only affect the treadmill would have on you is the resistance of the bearings, something that you could easily overcome by lightly holding onto the rail. if you tried to hold on to the rail with your feet planted on a 10mph moving treadmill, you'd get pulled off.

there's two different types of speed in this equation. forward speed of the plane (which is relative to the earth) and the speed of this treadmill. when the experiment starts, they are both going 0. the plane is sitting on the treadmill, and the treadmill is not moving. the plane then starts to move forward at a given speed (relative to the earth, not the treadmill), and continues to gain speed like it normally would on a take off. the speed relative to the earth and the wind it needs for lift is not affected by the treadmill.

imagine if this plane had hover-jets instead of wheels, then it would take off no problem, right? because then there'd be 0 friction for the treadmill to have any affect on the plane. well the bearings and tires of the plane have only a very small amount of friction that gets placed on the plane, something that the jet can easily overcome for takeoff.

i vote we lock this thread until january 30th

 

you guys are talking about two different speeds
an airplane has a ground speed and an air speed
which one the conveyer is matching is what needs to be pinpointed

 

that's what i said. but anyway, i see where i misunderstood your original comment, that you apparently edited out anyway

 

Yeah, i did. I decided it wasn't relevent.

 

THere is only one speed though, unless you are looking at the speed of the wheels spinning. The speed it moves in relation to the earth. Just like every other measure of speed.

 

speed relative to someone standing on the ground (no conveyor)