Answer:
A) R = 190.42 Ω
B) P = 5.325 W
Explanation:
We are given;
Total power;P_tot = 7.1 W
Voltage;V = 26 V
A)We are told that while the battery is still connected, one of the resistors is heated, so that its resistance doubles.
Thus, the power is doubled.
Now, formula for power is;
P = IV
Thus, since power is doubled, we have;
P = 2(IV)
Now, formula for current is; I = V/R
So, P = 2V²/R
Making R the subject, we have;
R = 2V²/P
In this question, P is p_total = 7.1 W
Thus;
R = (2 × 26²)/7.1
R = 190.42 Ω
B) Now, the resistance of the resistors are R and 2R.
Formula for power in this context is;
P = V²/R
Thus,
Total power delivered to the resistors is;
P = V²/R + V²/2R
P = 3V²/2R
P = (3 × 26²)/(2 × 190.42)
P = 5.325 W
