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Heating a pot of water with an electric heater with resistance R1 takes t1min to boil, and heating the same pot of water with an electric heater with resistance R2 takes t2min to boil. The time ratio of heating the same pot of water with two resistors in series to heating the same pot of water with two resistors in parallel is () and the power supply voltage remains unchanged A t1+t2/t1t2 B (T1 + T2) square / t1t2 C t1t2/t1+t2 D T1 + T2 / (T1 + T2) square
Suppose the mass of water is m, the specific heat capacity is C, and the power supply voltage is u, then u ^ 2 / R1 = CMT1, u ^ 2 / r2 = CMT2, so R1 = u ^ 2 / (CMT1), R2 = u ^ 2 / (CMT2), and the total resistance after series connection is r = R1 + R2 = u ^ 2 / (CM) * [(T1 + T2) / (t1t2)], so the total resistance after parallel connection is r = R1 * R2 / (R1
The specification of an electric heater is 220V, 880W. What is the resistance of the electric heater when it works normally
R=P/U*U
I have 300 ohm, 200 ohm, 510 ohm and 470 ohm resistance, but I need 1000 ohm resistance
How to connect these four kinds of resistors to get 1000 ohm resistance
300 series 300 Series 200 Series 200 = 1000
200 in parallel 200 in series 300 in series 300 in series 300 = 1000
wait
RELATED INFORMATIONS
- 1. The resistance of a resistance wire is 1000 ohm. The maximum allowable voltage is 1a. When the voltage is 220 V, how to make a maximum power electric heater
- 2. An electric fan, a TV set and an electric iron with the specifications of "220 V & nbsp; 100 W" are respectively connected into the 220 V circuit. The power on time is the same, and the heat generated by the current passing through them is the most: () A. Electric iron B. TV C. electric fan D. as much
- 3. In the case of only 380V power supply, two incandescent lamps marked with 220V, 100W and 220V, 25W are used in series. What is the actual power consumption of these two bulbs [set filament resistance and rated state the same]
- 4. As shown in the figure, the specification of the electric iron is "220 V, 40 W". When s is closed, the electric iron works normally; when s is disconnected, the electric iron is in the preheating state. In order to make the power of the electric iron during preheating only 1 / 4 of the rated power, ask: (1) what kind of resistance should be selected? (2) how much electric power is consumed by the whole circuit during preheating
- 5. If the lamp marked with "220 V & nbsp; & nbsp; 100 W" is connected to the home circuit and energized for 1 hour, the work done by the current is______ J. Its resistance is______ Ω．
- 6. A 100W bulb and a 15W bulb are connected in series in a voltage of 220V (rated voltage). Which bulb is on and why
- 7. The lamp L1 marked with 220 V, 100 W and the lamp L2 marked with 220 V, 25 W are connected in series in the same circuit, and they are actually eliminated The lamp L1 marked with 220 V, 100 W and the lamp L2 marked with 220 V, 25 W are connected in series in the same circuit. In order to ensure the safe use of the two lamps, what is the maximum voltage applied at both ends of the circuit
- 8. A lamp is marked with 220V 100W, B lamp is marked with 110V 100W, when they light up in their respective circuits, why do they consume the same amount of electric energy at the same time
- 9. If L1, L2 and L3 are marked with "220V & nbsp; 100W", "110V & nbsp; 100W" and "36V & nbsp; & nbsp; 100W" respectively, and they all light normally, then () A. L1 is the brightest B. L2 is the brightest C. L3 & nbsp; is the brightest D
- 10. One degree of electricity can supply five "220 V, 40 W" electric lamps for several hours Thank you. The final answer is five hours
- 11. Resistor R1 is 12 ohm. Connect it in series with R2 and connect it to 8V power supply. It is known that the voltage at both ends of R2 is 2V. Calculate the current in the circuit
- 12. As shown in the figure is the internal circuit structure diagram of a household electric heater, in which R1 and R2 are heating resistance wires (R1 > R2). The following four connection modes of resistance wires can make the electric heater provide different heating power, in which () A. The connection mode of a has the smallest heating power, the connection mode of B. B has the smallest heating power, the connection mode of C. C has the largest heating power, and the connection mode of D. D has the largest heating power
- 13. If an electric furnace is connected to a circuit with a voltage of 220 V and the energy consumed in 10 min is 6.6 times 10 quintic J, the electric power of the electric furnace is [] The current through it is [], and the resistance of the furnace wire is
- 14. Bulbs L1 and L2 are marked with "22ov 25W" and "220V 15W" respectively. If the two bulbs are connected in series, the voltage ratio of the two lamps is? The ratio of the actual power consumed is?
- 15. The word "220 V, 40 W" is marked on the white woven lamp. 220 V indicates the voltage of the light bulb, called. Voltage, 40 W. the electric power of the light bulb is called power
- 16. Xiaoming's family has electric fans and incandescent lamps with rated power of 40W. They work normally for the same time____________ Generate heat Many. Xiaoming's family also has a "220V 1500W" electric water heater, which is separately connected in the circuit. It is found that the aluminum plate on the electric energy meter (as shown in the figure) rotates 125 revolutions in 121s, and the electric water heater consumes a lot of energy____________ J's electric energy, the actual voltage of his home is____________ 5. (the resistance value of the resistance wire in the electric water heater remains unchanged)
- 17. The electric power of an electric heater is 1500W. If the electric heater works for 20min every day, it will consume electric energy for 30 days______ Degree
- 18. As shown in the figure, it is a schematic diagram of the electric blanket circuit. R0 is the resistance wire in the electric blanket, R is the resistance in series with the resistance wire of the electric blanket, the electric blanket is marked with "220 V & nbsp; 100 W", and S is the switch that controls the electric blanket in the heating state or the heat preservation state. (1) use the learned common formula to explain whether the electric blanket is in the heating state or the heat preservation state when the switch S is disconnected? (2) If it is required that 60 J of electric energy is converted into internal energy per minute when the current passes through the resistance wire R0 during heat preservation, what is the resistance value of the resistance R?
- 19. In that year's senior high school entrance examination, the power supply voltage was 4.5V in the experiment of "measuring the electric power of small bulbs" The rated voltage of the small bulb is 2.5V and the resistance is about 10 Ω
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