I was guessing poster tack myself, since it's more likely to hold its stickiness after getting crud all over it. But I wouldn't know for sure without trying it. Hopefully the OP will have time to mess around.
Light materials? After all, F = ma => a = F / m. Most cars I googled used wood and string, both light, with something thin and light for the wheels.
Another issue they seem to face is wheel spin. So you want a high friction material around the rim of the wheels to avoid slippage. Rubber is...
That first number should be the density of water. Normally I see it written as the greek letter rho (looks like a rounded lowercase p). P1 - P2 = ΔP = dgΔh.
It looks like in this situation the pressure difference is negative, as the hot expanded air is being used to suck water into the tube...
1. Complicated, but very brief anyway since the mass to be accelerated is so low. Soon you hit a constant flow; see #3. You should still verify that the system rapidly reaches the velocity in #3. Just use F=ma to find the initial acceleration.
2. Area x velocity, naturally.
3. Yes, when...
Pressure at the bottom of the mile high tube will be incredibly high. Pressure in the ocean will remain unchanged. And then the water in the tube will fall to the level of the ocean, and the pressure in the tube will drop to that of the ocean. Pressure in the ocean wills still remain unchanged.
Polarized light isn't as bright, that may be it. If anything changing part of the light into heat and reducing the amount of light energy (which is relatively low entropy) may increase overall entropy.
The wire's DC resistance stays the same, but generating the magnetic field created by the coils resists changes in current because it takes energy to change the strength of the magnetic field. So when the current is changing the total impedance (wire resistance + coil impedance) will increase...
Use whatever is cheapest and strong enough. The weight of the material is only confusing the matter. After the generator gets up to speed it has no effect whatsoever. At that point the only opposing forces are friction and the generator attached to the turbine. But the above post is a good...
Every ~2.3 feet in elevation difference equals 1 psi. You might have a slope of 1-2%, 1-2 feet per 100 feet of horizontal difference, and it would appear level. Or etc.
But the air pressure at the hydrant is exactly equal to the water pressure at the hydrant. It's the other location and...
Volume has a linear effect on power consumption while velocity has a cubic effect. To get the most cooling with the least power consumption you want high volume, low velocity. That means getting a nice wide fan or multiple fans stacked together - ideally as wide and high as yourself plus the...
Gravity is what propels the car forward,which is proportional to weight. a = F / m = mg sin theta / m = g sin theta. Where theta is the slope of the ground (level is zero). Friction is what holds the car back, which is also proportional to weight. a = F / m = umg cos theta / m = ug cos...
Ah, I didn't notice the 100m length, that'll add a little pressure loss. For some reason I thought it was a short hose. To convert back and forth between meters of water and other forms of pressure, just find the pressure of a column of water X meters high. For example, 1 meter high of water...
Seems like it should be right, though I haven't double checked it thoroughly. Just remember that the beam equation is only valid for small deflections. For bending stress I assume you're using S = Mc/I.