Question

Electrical equipment in an office takes a current of 13 A from a 240 V supply.
Estimate the cost per week of electricity if the equipment is used for 30 hours each
week and 1 kWh of energy costs 7p​

Answer 1

current : 13 A

potential difference = 240 v

power = 13 × 240 = 3120 w

power = 3.12 kw

time used = 30 × 7 = 210 hours

electrical energy consumed. = p×t

E = 3.12 × 210 = 655.2 kWh

1 kWh = 7p

655.2 kWh = 7 × 655.2 = 4586.4 p

Answer 2

Answer:

655.2p per week

Explanation:

Given:

I= 13A

V=240

t= 30 hrs per week

Solution:

P = V x I

P = (13)(240)

P = 3120W

Convert to Watt to kilo:

3120W/1000 = 3.12kW

Energy:

E = P x t

E = 3.12 x 30

E = 93.6 kW-hr

Estimate Cost:

C = 93.6kW-hr x 7

  = 655.2p per week