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In the home circuit, the voltage must be 220 V, and the resistance of the electric stove is very large. According to P = u / R, the power should be very small, but why is the power of the electric stove very large? Moreover, the higher the resistance of other electrical appliances, the greater the power?
The power of the electric furnace is actually thermal power, not electrical power. It should be calculated by Joule's law. Therefore, the greater R is, the greater the thermal power is
Electric furnace is heated, so p = u / R cannot be used. This formula already admits ohmic rate, so p = I r should be used, which can explain why! Isn't r Ohm's law when p = I? Family circuit is parallel, should not use p = I side r! This is the formula of thermal power. It's in the book! If the resistance is larger and the current is smaller, how can we determine that the power must be larger? It seems that the electric stove doesn't follow Ohm's law! ... unfold
Electric furnace is heated, so p = u / R cannot be used. This formula already admits ohmic rate, so p = I r should be used, which can explain why! Question: isn't r Ohm's law when p = I? R = parallel circuit should not be used!
For the circuit wires in newly-built residential buildings, copper wires are generally used instead of aluminum and iron wires, while silver wires are used in some important instruments,
It's only related to the conductivity. I remember that the conductivity from low to high is gold, silver, copper and iron. If the conductivity is low, the resistance of the conductor with the same cross-sectional area and length is small, and the effect of signal transmission is good. See the formula of resistance and conductor length and cross-sectional area. Of course, besides the conductivity, the cost should also be considered. Therefore, the general key points, such as CPU
Question: is 2.5 square meter wire diameter 1.76 OK
2.5 square wire diameter is 1.76 OK. 2.5 square wire is the pure cross-sectional area of copper wire.. 1.76 / 2 * = * 3.14.0.88 * 0.88 * 3.14 = 2.4316. It's a little less than 2.5. So: wire 1.76 is 2.5 square. (mm)
Is the power of household appliances high with large resistance or high with small resistance?
All the household appliances are connected to the 220 V electric circuit, and the power P = u ^ 2 / R
If copper wire and manganin wire with the same length and thickness are connected in series, then ()
A. The resistance, current and voltage at both ends are equal. B. the resistance of copper conductor is small, the current is large, and the voltage at both ends is equal. C. the resistance of copper conductor is small, the voltage at both ends is small, and the current is equal. D. the resistance of copper conductor is large, the voltage at both ends is large, and the current is equal
The resistance of conductor is related to the material, length and cross-sectional area of conductor. The length and cross-sectional area of copper conductor and manganin conductor are the same. According to the material of conductor, the resistance of manganin conductor is large. In series circuit, the current is equal everywhere, so the current in the two conductors is the same. According to Ohm's law, u = IR, the voltage at both ends of manganin conductor is large. So a, B and D are wrong, C is correct
1.5 air conditioning wires, 4 square wires OK
The safety current of 1 square copper wire is 4 A, 4 square can withstand 16 A, and the current of 1.5 Pico machine is 6 A, so it is enough
Given the current 20mA, voltage 220V, resistance and power, which formula?
Ohm's Law: r = u / I
Electric heating formula for power calculation: P = UI = I2R = U2 / R
2 here is the square
In a series parallel circuit, when the voltage is constant, what is the relationship between the current and the resistance?
In series, the current is the same. In parallel, the current is inversely proportional to the resistance
How many catties of aluminum can 25 and 50 square aluminum cables produce? 9 broken lines
What is the number of cores? Aluminum output per kilometer: (50 * 2.7 * 3 + 25 * 2.7) * 0.9 = 425.25kg
(25 * 3 * 2.7 + 16 * 2.7) * 0.9 = 221.13kg
Microwave oven is a household appliance with high efficiency. A microwave oven marked with "220 V, 880 W" has a high resistance when it is in normal use______ Ω, the current through it is______ A. If it takes 15 minutes to cook a meal with it, it's better to cook a meal with it______ It's not enough
According to the meaning of the title, the resistance of u = 220V, P = 880W microwave oven is & nbsp; r = u2p = 220V × 220v880w = 55 Ω; the current through it is I = Pu = 880w220v = 4A; the power consumption is w = Pt = 0.88kw × 15 × 160H = 0.22kw · H = 0.22 degree, so the answer is 55, 4, 0.22
RELATED INFORMATIONS
- 1. Does the total voltage and current in parallel circuit change with the resistance
- 2. Can two 2.5 wires be used together as a 6 square one? Is the current passing through the two wires the same? It's better to have theory, authoritative theory. I'm adding points
- 3. Know a thing power is 1500W, voltage is 220V, how to find its resistance? Fine formula!
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- 7. The voltage at both ends of a conductor is 3V, the current passing through it is 0.3A, and its resistance is 10 Ω. When the current passing through the conductor is 0.5A, its resistance is Ω
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- 9. The size of a household electric iron is 220 V 800 W. it can generate J heat and use kwh electric energy after 10 minutes of normal operation
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- 11. How much copper does a meter of 3 * 120 cable contain?
- 12. When the voltage at both ends of the conductor is 6V, the current passing through it is 0.6A, and the resistance is 10 ohm. If the voltage at both ends of the conductor is 3V, what is the current and resistance of the conductor
- 13. 1. A bulb connected to a 220 V circuit, the current through the bulb is 0.5 A, the power on time is 1 h, how much energy does it consume? How many kilowatt hours?
- 14. What is the specification of 2 * 2.5 square wire?
- 15. When the constant voltage U is applied to both ends of a metal wire with uniform thickness, the current intensity passing through the metal wire is I, and the average rate of directional movement of free electrons in the metal wire is v. if the metal wire is elongated to make its length twice the original length, throw it to both ends and apply the constant voltage u, then The rate of directional movement of free electrons is v / 2 I know that the current becomes a quarter. Why does the rate become a half?
- 16. 1. The actual power of a 220 V, 100 W light bulb is 2 when it is 110 v. two 220 V, 100 W light bulbs are connected in series in the circuit to calculate the power consumption after 1 min
- 17. The sliding resistor is connected to the circuit by changing the resistance______ To change______ &The size of the
- 18. A measuring cylinder is 1m high with a bottom area of 40DM and a vertical slender tube with a length of 1.2m and a cross-sectional area of 5cm A measuring cylinder is 1m high with a bottom area of 40DM and a vertical slender pipe with a length of 1.2m and a cross-sectional area of 5cm. When the cylinder and the long pipe are filled with water, what are the water pressures on the upper and lower bottom of the cylinder and the gravity of the water in the cylinder and the pipe? (g = 10N / kg)
- 19. There are three electrical appliances. The voltage of electric fan, electric bulb and electric heater is 220 V, and the electric power is 60 W. when the rated voltage is fixed, the heat generated is relatively small
- 20. If the words "220V 10A (20a)" are marked on a household electric energy meter, it is allowed in the household circuit