Solve the problem.
-The voltage across a resistor is jointly proportional to the resistance of the resistor and the current flowing through the resistor. If the voltage across a resistor is 12 volts for a resistor whose resistance is 6 ohms and when
The current flowing through the resistor is 2 amperes, find the voltage across a resistor whose resistance is
9 ohms when the current flowing through the resistor is 8 amperes.
A) 72 V
B) 48 V
C) 18 V
D) 16 V

Question

Quizplus · Accepted Answer

Let V be the voltage across the resistor, R be its resistance and I be the current flowing through it.
According to the problem, V is jointly proportional to R and I, which can be expressed as:
V = k*R*I   where k is the proportionality constant.
To find the value of k, we can use the given values:
When V = 12, R = 6 and I = 2, we have:
12 = k*6*2
Solving for k, we get:
k = 1
Now we can use this value of k to find the voltage V2 for the second scenario:
When R2 = 9 and I2 = 8, we have:
V2 = k*R2*I2
V2 = 1*9*8
V2 = 72
Therefore, the voltage across the resistor whose resistance is 9 ohms when the current flowing through the resistor is 8 amperes is 72 volts. The best choice is A.

Solve the Problem. -The Voltage Across a Resistor Is Jointly Proportional to the Proportional