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

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

In figure a, only resistance R2 works; in Figure B, the two resistors are in series; in Figure C, only resistance R1 works; in Figure D, the two resistors are in parallel. When the two resistors are in series, the circuit resistance is the largest and the electric power is the smallest; when the two resistors are in parallel, the resistance is the smallest and the electric power is the largest. Therefore, B and D are selected

It takes the shortest time to make an electric heater with two resistance wires of R1 and R2 (R1 > R2) to raise the same temperature of water with the same mass
1. Is it necessary to connect two resistance wires in series or in parallel?
2．P＝U2＼R
Q＝I2RT
How should these two formulas be explained in terms of resistance?
If it is parallel, the resistance of the total circuit is not very small? Then which formula is used in this case? Who can summarize it for me
Thank you, also, some relatives won't, just won't, don't give me a few scribble!

1. Do you want to connect two resistance wires in series or in parallel? A, in parallel. Because the applied voltage is constant, the power P = u ^ 2 / R. the smaller R (in parallel), the greater the current, so the higher the power. 2. P = u ^ 2 / R. if the applied voltage is constant and the resistance is changed in two cases, use this formula. P = I ^ 2 * r

Resistance R1 = 7ohm, R2 = 5ohm, connected in series at both ends of 12V power supply. At this time, the total resistance of the circuit is - ohm, and the voltage at both ends of R2 is - volt
And connected in 3V circuit, parallel
The total resistance is - ohm, the current through the trunk is - A, and the ratio of the current through R1 and R2 is——

12 5 1.03 5:7