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Anonymous users2024-02-12The frequency of a sound is called pitch.
The magnitude of loudness is related to the amplitude of the object's vibration and its distance from the emitter.
Timbre refers to the sensory properties of sound.
Cold light source: cold light source fireflies, neon lights, LEDs
Thermal light source: incandescent lamp.
Point light sources and parallel light sources are represented as radial and parallel lines, respectively.
Definition of the speed of light: The speed at which light waves or electromagnetic waves travel in a vacuum or medium.
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Anonymous users2024-02-111.The frequency at which the sound source vibrates.
2.The amplitude of the vibration is the distance from the sound source.
3.Forgot. 4.Fluorescent electric light.
5.Not easy to explain.
6.The velocity of light in a vacuum.
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Anonymous users2024-02-101. The level of sound frequency is called pitch.
2. Amplitude and distance from the sound source.
3. It refers to the sound characteristics of different vocal bodies, and the timbre of different vocal bodies is different when the tone and loudness are the same.
4. Fireflies; Torches, the sun.
5. Radiation, parallel lines.
6. The propagation speed of light in a vacuum.
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Anonymous users2024-02-091. The level of sound.
2. Amplitude and distance from the sound source.
3. Characteristics of sound. Generally speaking, the definition of timbre is not said.
4. Fireflies are cold light sources, and sun, torches, etc. are hot light sources.
5. The point light source is represented by a point, and the light emitted is not parallel. The light emitted by a directional light source is a parallel light, and the shape of the light source is not drawn, but only the parallel rays emitted by it.
6. The distance at which light travels in one second.
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Anonymous users2024-02-08According to the conditions given in the question, it can be seen that there is an inflow of air bubbles at the A hole. Because, the pressure at hole A is less than the pressure at hole hole.
There is water flowing out of the c-hole. This is because the pressure at hole C is stronger than the pressure at hole b.
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Anonymous users2024-02-07From q=sv, we can see that v does not change. Bernoulli's equation can be used, p+ gh = constant. So the high pressure at A is smaller. There are air bubbles entering. The low pressure is greater at C. There is water flowing out.
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Anonymous users2024-02-06Causes the ball to experience a force of magnitude (k is constant, v is the velocity of the ball) that always deviates from the center of the circle. This shows that this force has a negative charge at point o, and produces a coulomb repulsion force on -q, which always deviates from the center of the circle along the radius.
On the other hand, since the velocity of the two points at m, n is zero, it means that the direction of the resultant force of the electric field force on charge-q and the gravitational force of the ball is on the angular bisector of mon. From this, the magnitude of the electric field force eq can be calculated, and then e = q c can be calculated according to the formula, and q can be calculated.
As for the acceleration at point n, since both gravity and the uniform electric field force are known, the acceleration produced by the resultant force of these two forces along the tangent direction of the arc is the acceleration of the ball at point n.
Sorry, I didn't count it for you. Hopefully you'll figure it out for yourself. If it's really not good, I'll give you another explanation.
This is a question of an equivalent gravitational field.
Not necessarily. It depends on the shape of the glass.
If it is straight up and straight down, the pressure of the glass on the table is the pressure of the water on the bottom of the cup plus the pressure of the empty cup on the tabletop. >>>More
1 All 1, increase your vocabulary:
Read the text, the words in the text are very important. Look up word lists or ask classmates for words you don't know, but don't write them down in a book. Read it a few times, look it up every time you don't know it, and slowly memorize it. >>>More
1。The idea of solving this problem is that the impulse is equal to the amount of change in momentum. >>>More
Gravity is not equal to the gravitational pull of the Earth on an object. Due to the rotation of the earth itself, in addition to the poles, the objects in other places on the ground are moving in an approximate uniform circular motion around the earth's axis together with the earth, which requires a centripetal force directed perpendicularly to the earth's axis, and this centripetal force can only be provided by the earth's gravitational force on the object, and we can decompose the earth's gravitational force on the object into two components, one component f1, which points to the earth's axis, and the magnitude is equal to the centripetal force required for the object to move in an approximate uniform circular motion around the earth's axis; The other component g is the gravitational force on the object, where f1 = mw2r (w is the angular velocity of the earth's rotation and r is the radius of rotation of the object), and it can be seen that the magnitude of f1 is zero at the poles, increasing with the decrease of latitude, and the maximum f1max is in the equatorial region. Because the centripetal force of the object is very small, in general, it can be approximated that the gravitational force of the object is equal to the gravitational force, that is, the influence of the rotation of the earth can be omitted in general. >>>More
In two cases, the increase is obvious on the main road, and the increase on a certain branch road will also increase the resistance of this part, as in the example of 1 ohm and 100 ohms: the original resistance is 100 101 ohms, if it increases by 1 ohm, then it will be closer to the increase (he to a few ohms), this is the trend, if it increases by 100 ohms, then it also increases, this is less obvious than the former, the amplitude is not very high, you can use the mathematical formula to push down r=r1r2 (r1+r2), so that it is clearer.