To tackle this problem, we need to analyze the circuit involving the voltmeter, ammeter, and the resistor. Let's break it down step by step to find the value of I/4.
Understanding the Circuit Components
We have two key measurements from the circuit:
- The voltmeter reading between points C and D is 140 V.
- The ammeter reading when connected between the same points is 21 A.
Applying Ohm's Law
Ohm's Law states that V = I × R, where V is voltage, I is current, and R is resistance. From the voltmeter reading, we know the voltage (V) across the resistor is 140 V. When the ammeter is connected, it shows a current (I) of 21 A flowing through the circuit.
Calculating Resistance
Using Ohm's Law, we can calculate the resistance (R) of the resistor connected between points C and D:
Rearranging Ohm's Law gives us:
R = V / I
Substituting the known values:
R = 140 V / 21 A = 6.67 Ω
Finding the Current I
Now, we need to determine the current I flowing through the resistor r when it is connected between C and D. Since we already have the current reading from the ammeter, we can conclude that:
I = 21 A
Calculating I/4
To find the value of I/4, we simply divide the current by 4:
I/4 = 21 A / 4 = 5.25 A
Final Result
Thus, the value of I/4 is 5.25 A. This calculation illustrates how we can use basic principles of electricity, such as Ohm's Law, to analyze and solve circuit problems effectively.
