In a series circuit, the power source is 9-volt battery and three resistors.

R1=7ohm
R2=9ohm
R3=2ohm

What is the total resistance in this series circuit?
What is the current?

Please help I don't understand this!, Thank you

If the resistors are all in SERIES then the total resistance is the sum:

7 + 9 + 2 = 18 ohms

i = V/R = 9/18 = 0.5 amperes

To determine the total resistance in a series circuit, you need to add up the individual resistances of each component. In this case, the total resistance (RT) can be calculated by summing the resistances of R1, R2, and R3.

RT = R1 + R2 + R3
= 7 ohm + 9 ohm + 2 ohm
= 18 ohm

Therefore, the total resistance in this series circuit is 18 ohms.

To find the current in a series circuit, you need to divide the voltage provided by the power source by the total resistance. In this case, the power source is a 9-volt battery.

I = V / R
= 9 V / 18 ohm
= 0.5 A (Amperes)

Hence, the current in this series circuit is 0.5 Amperes.