1)If a resistor is added to a parallel circuit, the equivalent resistance:
A)increases
B)decreases
C)remains the same
D)becomes zero
I got B
2)A 10.0 resistor, 20.0 resistor, and 25.0 resistor are connected in series across a 110-V supply. Calculate the current in the circuit.
A)2.0 A
B)4.5 A
C)55 A
D)11 A
V source/R
110/55
answer= A
both correct.
For the following series circuit, compute the power in R1, R2, and R3 if the circuit values are E = 24 volts, R1 = 8, R2= 12, and R3 = 28.
For question 1, the correct answer is A) increases. When a resistor is added to a parallel circuit, it creates an additional pathway for the current to flow through. This results in more current flowing through the circuit, which, in turn, increases the total resistance.
To understand this concept, you can visualize a parallel circuit with two resistors connected in parallel. Without the additional resistor, the current would divide between the two resistors. However, when the third resistor is added in parallel, it creates an extra pathway. Now the current is divided among three resistors, which increases the overall resistance.
For question 2, the correct answer is B) 4.5 A. To calculate the current in a series circuit, you can use Ohm's Law, which states:
V (voltage) = I (current) x R (resistance).
In this case, you have three resistors connected in series, so the total resistance (R) is the sum of all the resistances:
Total resistance (R) = 10.0 Ω + 20.0 Ω + 25.0 Ω = 55.0 Ω.
Given that the voltage (V) is 110 V, you can rearrange Ohm's Law to solve for current (I):
I = V / R = 110 V / 55.0 Ω = 2.0 A.
Therefore, the current in the circuit is 2.0 A.