Consider the three circuits shown above. All the resistors and all the batteries
ID: 1642762 • Letter: C
Question
Consider the three circuits shown above. All the resistors and all the batteries are identical. The current through a resistor is the same in circuits A and B. The total power dissipated in circuit C is twice the total power dissipated in circuit B. The power dissipated in circuit A is twice the power dissipated in circuit B. The current through a resistor is the same in circuits A and C. The voltage across a single resistor in circuit C is twice the voltage across a single resistor in circuit B. Tries 0/30Explanation / Answer
first circuit:
total resistance=R
voltage=V
current=V/R
circuit B:
R and R are in series.
net resistance=R+R=2*R
current=V/(2*R)
circuit C:
R and R in parallel.
net resistance=R*R/(R+R)=R/2
current in the circuit=V/(R/2)=2*V/R
then:
first statement is false as current through a resistor is different for circuit A and circuit B.
second statement:
power dissipated in circuit C=voltage^2/total resistance
=V^2/(R/2)=2*V^2/R
power dissipated in circuit B=V^2/(2*R)
so total power dissipated in circuit C is 4 times total power dissipated in circuit B.
hence the given statement is false.
third statement:
power dissipated in circuit A=V^2/R
hence it is double of power dissipated in circuit B.
hence the statement is correct.
fourth statement:
voltage across R in both circuit A and circuit C is same as V.
hence current through a resistor is same.
hence the statement is true.
fifth statement:
voltage across a single resistor in circuit C=V
voltage across a single resistor in circuit B=(V/(R+R))*R=V/2
hence the statement is correct.
so answers are:
false
false
true
true
true