There are three resistors marked with 100 ohm 4W 12.5 ohm 8W 90 ohm 100W respectively. The maximum voltage allowed to be added when they are connected in series is () v. they are allowed to be added when they are connected in parallel

There are three resistors marked with 100 ohm 4W 12.5 ohm 8W 90 ohm 100W respectively. The maximum voltage allowed to be added when they are connected in series is () v. they are allowed to be added when they are connected in parallel

The current of series circuit is constant
According to the electric power formula w = I ^ 2 * r
1 resistance allowable over current = 0.2 a
2 resistance allowable over current = 0.8 a
3 resistance allowable over current = 1.1 A
Minimum allowable over current in series circuit = 0.2 a
Ohm's law v = I * r
Maximum voltage = 0.2x (12.5 + 90 + 100) = 40.5V

Resistance R1 and R2 are marked with specifications of "100 Ω, 4W" and "12.5 Ω, 8W" respectively. After they are connected in series, the maximum voltage they can withstand is______ V．

Resistance R1 is marked with "100 Ω, 4W", according to P = I2R, the rated current is: I1 = p1r1 = 4100 = 0.2A, resistance R2 is marked with "12.5 Ω, 8W", according to P = I2R, the rated current is: I2 = p2r2 = 812.5 = 0.8A, after they are connected in series, the maximum current I of the circuit is 0.2A, so the maximum voltage of the series current is: u = I (R1 + R2) = 0.2 × (100 + 12.5) = 22.5v, so the answer is: 22.5v 5．

Resistor R1 and R2 are respectively marked with specifications of "100 ohm, 4W" and "12.5 ohm, 8W". After they are connected in series, how much voltage can they withstand
I1 = 0.2A, I2 = 0.8A, so I string = 0.2A

When two electric resistors are used in series, they can only be used according to the rated current (power) of 4W resistor, and the maximum withstand voltage is 22.5v. When the current of series circuit is greater than 0.2A, it exceeds the rated power of 4W resistor, and the resistor will be burned after a long time

The rated power of an electric iron is 100W, and the normal working resistance is 121 Ω. What is the rated voltage of the circuit? What is the power consumption when it works at 88v for 10min

1) U = under root sign (p * r) = 110V
2) W=(U'^2/R) *T=64*600=38400J