Question

A hot plate of an electronic oven, connected to a 200 V line. It has two resistors coil A and B each of the 30 ohm which may be used separately, in series or in parallel. Find the value of the current required in each three cases ​

Answer 1

CASE 1

potential difference= 200 V

resistance of each wire=30 ohm

by ohm's law V=IR

so, I=V/R

R=30 ohm

now, I=V/R

I=200/30

I=6.7A

CASE 2

we know that in series combination equivalent resistance is given by

Rs=R1+R2

Rs=30+30

Rs=60 ohm

now,I=V/Rs

I=200/60

I=3.4 A

CASE 3

we know that in parallel combination equivalent resistance is given by

1/Rp=1/R1+1/R2

1/Rp=1/30+1/30

1/Rp=1/15

1/Rp=0.67

now,I=V/Rp

I=200/0.67

I=298.50 A