Aetol
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Why does a lot of water vapour come suddenly after the heat source of boiling water is removed?
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What you are seeing is not actually vapor - vapor is invisible. The mist seen above boiling water, commonly but inaccurately called vapor, is actually made of tiny droplets of liquid water, formed ...

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Questions on Non-Inertial Reference Frames
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2 votes

It is in fact not possible to distinguish between these two situations. This observation is called the equivalence principle. It is the basis of general relativity. Note that this principle is stated ...

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Small Angle Approximation for Simple Pendulum
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It seems like the origin is not P, but the point where the pendulum intersects the vertical axis. As a result the coordinates are: $x = L \sin(\theta)$ $y = L - L \cos(\theta)$ Which gives us: $\...

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Altering Young's double slit experiment due to observation
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It depends on what, exactly, is observed. In the standard version of the experiment, only the position of the electrons as they hit the screen is detected. In this case there are interference patterns....

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Can lightning bend metal?
1 votes

The intensity of Earth's magnetic field is 25 to 65 µT. The electric current of a typical lightning strike is about 30 kA. The resulting Laplace force is around 1 Newton per meter of pole. A pole or ...

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Would it generate a lift if wind is circulating inside a nearly closed tube?
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1 votes

No, there won't be lift. The Bernouilli effect will draw some air through the hole until the increased air density balances out the Bernouilli effect and the pressure is the same inside and outside. ...

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The acceleration of the point of contact, when a solid disc is rolling on a plank
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The motion of the disc is governed by $m_d a_d = F - F_c$ with $F_c$ the contact force between the disc and the plank. The motion of the plank is governed by $m_p a_p = F_c$. Finally, the rotation ...

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Centrifuge Artificial Gravity?
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If you look carefully, you'll notice wires attached to the person, as well as a boom above him that follows him as he walks. The wires are more apparent in the closeup (starting at 0:24), especially ...

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At terminal velocity, acting upon a still object, would the impact of an impact-grenade cause more or less force than the explosion?
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An object has a kinetic energy equivalent to its own mass' worth of TNT when it is moving at ~3 km/s. That is much higher than any terminal velocity, so unless the grenade contains very little ...

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How do we know that light cannot travel faster than it does?
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We used to think it could. Experiments proved that wrong. In the 19th century, it was widely believed that light, being wave-like, must be propagating through a medium that permeates the universe, ...

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Where does laser reflection (1) come from?
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The glass sends back light in two different ways. (2) is scattering of the laser light. This is correctly depicted on the drawing: light is sent back in all directions. This is a new source of light ...

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How does a rocket obey Newton's third law?
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Yes, the imbalance of force in the combustion chamber explain how a rocket works. The hot expanding gases push against the top of the chamber, but not the bottom since it's open, and so the rocket is ...

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