Answer:
15volts
Step-by-step explanation:
According to ohms law, the current passing through a metallic conductor at constant temperature is directly proportional to the potential difference across its ends. Mathematically,
E = IRt
E is the source voltage
I is the total current
Rt is the effective resistance.
Before we can get the voltage drip across a load, we must know the current flowing through it.
Given E = 90V
Rt = 5+10+15 (for a series connection)
Rt = 30Ω
I = E/Rt
I = 90/30
I = 3A
Note that In a series connected circuit, same current but different voltage flows through the circuit.
Therefore the current in the 5Ω resistor is also 3A.
To get the voltage drip across the 5Ω resistor we use the formula
V=IR
V = 3(5)
V = 15volts