The rated voltage is 220 V, the frequency is 50 Hz, the rated power is 880 W, and the volume is 2 L. what is the resistance of this electric kettle when it works normally? Please write down the process,

The rated voltage is 220 V, the frequency is 50 Hz, the rated power is 880 W, and the volume is 2 L. what is the resistance of this electric kettle when it works normally? Please write down the process,

The electric kettle is a pure resistance circuit
R = u ^ 2 / P = (220 V) ^ 2 / 880 w = 55 Ω

First simplify, and then evaluate: [(X-Y) 2 + (x + y) (X-Y)] / 2x, where x = 3, y = 1

The original formula = (x2-2xy + Y2 + x2-y2) △ 2x = (2x2-2xy) △ 2x = X-Y, then when x = 3, y = 1, the original formula = 3-1 = 2

The resistance of an electrical appliance is 400 Ω, and the maximum allowable current is 0.5A. If the electrical appliance is connected to the circuit with current of 1.5A, it can work normally,
How large a resistor must be connected in parallel?

The current at both ends of 400 Ω resistor is 0.5A, and the voltage at both ends is: u = RI = 400.0.5 = 200V. (resistance power P = u.i = 100W)
To increase 1A current, the resistance to be paralleled r = u △ 1A = 200 △ 1 = 200 Ω. (resistance power P = u · 1A = 200W)

As shown in the figure is a plane schematic diagram of a machine part with rectangular outline. According to the dimensions in the figure (unit: mm), the distance between the centers of two circular holes a and B is calculated as______ mm．

∵AC=150-60=90mm，BC=180-60=120mm，∴AB=AC2+BC2=1202+902=150mm．

What does w mean in physics

Represents watts as a unit
As a physical quantity, it can express work or angular velocity

1+3+9+27+…… What is 3 ^ n equal to?

Let 1 + 3 + 9 + 27 + 3^n=N
3N=3+9+27+…… +3^n+3^(n-1)
3N-N=3^(n-1)-1
2N=3^(n-1)-1
N=(3^(n-1)-1)/2

When a circuit is connected to a 200 ohm bulb, its current is 1a. If a 160 ohm electric iron is connected in parallel
What is the current through the electric iron?
What is the total current of the circuit?
Please write the formula
The resistance is wrong. It should be a 240 ohm bulb

The voltage is 200 Ω × 1A = 200V
Because the voltage of the parallel circuit is equal (because you did not mention the position of this circuit in the specific circuit, so it can only be regarded as the bulb is directly connected to the power supply), the current of the electric iron is 200V △ 160 Ω = 1.25A
The total current is 1A + 1.25A = 2.25A
If this part of the circuit is in other places in the circuit, it should be treated differently

14 is a multiple of 7, 21 is a multiple of 7, and the sum of 14 and 27 is a multiple of 17. What rules do you find?
It's the last untitled topic in the math book Page16 of the people's education press.

If a is a multiple of N and B is a multiple of N, then a + B is also a multiple of n

What is the relationship between the total power of two different resistors in series and in parallel?
For example, series connection or parallel connection, why?

This problem is hard to define, but power P = UI
If it is a pure thermal effect circuit, the voltage is equal
The power in series is less than that in parallel
P = u ^ 2 / r the total resistance in series is larger than that in parallel, so the power in series is smaller
For non pure resistance circuit, if the voltage is equal, the power of series circuit is lower than that of parallel circuit,
If we understand this angle, we can't use Ohm's law to understand it. We can only have p = UI, which can be found in all cases

Given a + B + C = 3, a & # 178; + B & # 178; + C & # 178; = 3, then a ^ 2007 + B ^ 2007 + C ^ 2007=_______

A: it is known that a + B + C = 3, a & # 178; + B & # 178; + C & # 178; = 3
A = 1, B = 1, C = 1
Then a ^ 2007 + B ^ 2007 + C ^ 2007 = 1