Question

For a heater rated at 4 kW and 220 V, calculate
(a) the current
(1) the resistance of the heater,
(c) the energy consumed in 2 hours, and
(d) the cost it 1 kWh is priced at 4.60​

Answer 1

Answer:

Given

P=4kW,V=220V

(a) I=?

Power=VI=250×I

4000=250×I

I=16amp

(b) R=?

P=I

2

R

P=16

2

×R

R=4000/16

2

R=15.25ohm

(c) Energy consumed in two hour =P×t

=4×2

=8kW−hr

(d) If 1kWh=Rs.4.6

total cost =8×4.6=Rs.36.8