Question

Two identical resistors each of resistance 10 ohm are connected 1) in series 2) in parallel, in line to a battery of 6volts. Calculate the ratio of power consumed in the combination of resistors in the two case

Answer 1

1)in series
10 + 10 = 20Ω
now find the current
I=V/R
 =6/20
 =.3A
now power
P1=V(I)
   =6×.3
  = 1.8W
2)in parallel
1/R=1/R+1/R
  =1/10+1/10
R  =5Ω
now current
I=V/R
 =6/5
 =1.2A
power
P2=V×I
  =6×1.2
  =7.2W

Ratio
P1/P2=1.8/7.2
          =.25W

Answer 2

Ratio: 1:4

Power in first case: v^2/r

=36/20

=1.8W

Power in second case: 36/5

=7.2W

Therefore ratio is 1.8:7.2

Which is 1:4

Thank you