Question

Q. An electric geyser rated 1500W, 250V is connected to 250V line mains. Calculate:.
i) electric energy drawn by it
ii) energy consumed by it in 50 hours
iii) cost of energy consumed if each unit cost Rs. 6.00

Answer 1

Power of geyser, P = 1500 W

Voltage of supply, V = 250 V.


i) P = VI

=> I = P/V = 1500/250
= 6 A.

current drawn by the geyser.

ii) Time = 50 h = 50 × 60 × 60 s = 180000 s

Energy consumed = Pt = 1500 × 180000

= 270000000 J.

= (270000000/3600000) kWh
= 75 kWh.

iii). Cost of 1 unit is Rs 6.

Energy consumed in 50 h is = 75 kWh
= 75 units.

Hence, cost of electricity used in 50 h

= 75× 6 = Rs 450

Answer 2

ANSWER :

Given : P ( power ) = 1500 W, V = 250V  ( V = Volt )

( I = Current )    

i) Current drawn,  

I = P/V = 1500/250 = 6A

ii) Electric energy consumed by geyser in 50 hours = Power × Time.

= 1500 × 50 = 75000 Wh = 75 kWh

Since , 1 kWh = 1 unit.

So, energy consumed = 75 units.

iii) Cost of one unit = Rs 6.00

Therefore , Cost of 75 units = Rs 75 × 6.00 = Rs 450.00