If r = 4.7K Ω and C = 22pf in RC oscillator circuit, how to calculate the oscillation frequency? Why is it 3.5-6mhz? Isn't it f = 1 / 2 * 3.14 * RC?

If r = 4.7K Ω and C = 22pf in RC oscillator circuit, how to calculate the oscillation frequency? Why is it 3.5-6mhz? Isn't it f = 1 / 2 * 3.14 * RC?

The formula you said is to calculate the resonant frequency. The calculation of the oscillation frequency is based on F = 1 / (1.1-1.5) RC, which is only an approximate value

What is the frequency characteristic of RC circuit

Frequency characteristic is divided into two parts: amplitude frequency characteristic and phase frequency characteristic. RC circuit contains capacitance, so the output is related to the angular frequency of input signal. Amplitude frequency characteristic is the relationship between mode and angular frequency, and phase frequency characteristic is the relationship between amplitude and angular frequency. For example, RC series: I (phasor) = u (phasor) / (R-J (1 / WC)), current mode I = u / (...)

(- 4 / 3A ^ 2BC) / (- 3AB) equals ()
A. 1A ^ 2C in 4 b.1ac in 4
C. 9A ^ 2C / 4 d.9ac / 4

(- 4 / 3A ^ 2BC) / (- 3AB) equals ()
=1 / 4 AC
Choose B

Use electric resistance 440 ohm, connect to the circuit to work, consume electric energy 66000j in 10 minutes. Try to find out the voltage at both ends of the electric appliance

(66000*440/60*10)^1/2=220

There are five same round wooden columns in the school corridor, with the perimeter of 9.42 decimeters at the bottom and the height of 4 meters. To paint these wooden columns, if you use 25 grams of paint per square meter,
How many kilos of paint do you need?

Bottom perimeter = 9.42 decimeters = 0.942 meters
The side area is: 0.942 × 4 = 3.768 square meters
Painting area: 3.768 × 5 = 18.84 square meters
Paint required: 25 × 18.84 = 471kg
Hope to help you!
If you don't understand, please ask. I wish you progress in your study!

What is the electric power of an electric appliance that consumes 0.2kwh of electric energy in 15min

W=0.2KWH T=15MIN=0.25H
P=W/T=0.2/0.25=0.8KW=800W

9A & # 178; - B & # 178; - 4b-4 factorization

Original formula = 9A & # 178; - (B & # 178; + 4B + 4)
=9a²-（b+2）²
=(3a-b-2)(3a+b+2)

If the total resistance is 1K ohm, then the resistance value of each resistance is_____ Oh?
I hope you can do me a favor and help me analyze it

4K Euro
1 / R total = 1 / R1 + 1 / r2 + 1 / R3 + 1 / R4 = 4 / R
R = 4R total = 4K Ω

The natural numbers 1 to 2004 are classified as 1 2 3 4 5 6 7 8 9 10 11 12 13 15 16 17······
Using a square frame to draw 9 numbers, can you make the sum of 9 numbers in a rectangular frame be 2007? If not, please explain the reason
A row of seven numbers - Baidu can't type that.

If the middle number is a, then the sum of the nine numbers is 9A
2007/(9a)=223/a
223 / 7 = 31,6
The sum of 9 numbers is 2007, and 223 in the middle is the sixth on line 31

Relationship between resistance and bulb brightness
The higher the temperature of the filament resistance, the more the brightness of the bulb changes
The higher the temperature of the filament, the change of the brightness and resistance of the small bulb?

If the voltage is constant, the power is inversely proportional to the resistance. The higher the resistance, the smaller the power. Carefully observe the 25W and 60W, 100W bulbs, you will find that the 25W bulb tungsten filament is the thinnest and the longest, the corresponding resistance is also the largest, 100W bulb tungsten filament is the thickest and the shortest, the corresponding resistance is also the smallest! The higher the temperature, the greater the resistance, may as well measure