Question

(a) A household uses the following electric appliances:

(i) Refrigerator of rating 400 watt for 10 hours each day.

(ii) Two electric fans of rating 80 watt each for 12 hours each day.

(iii) Six electric tubes of rating 18 watt each for 6 hours each day.

Calculate the electricity bill of the household for the month of June, if the cost per unit is

rupees 3.00.

(b)Two wires of same material and same length have radii R1 and R2. Compare their

resistances.​

Answer 1

Answer:

$49580()xy$

Answer 2

Answer:

1) Energy consumed by refrigerator 400 watt for 10 hours each day

P × T = 400w × 10h

400÷1000kw × 2h

= 0.8kwh

2) energy consumed by two electric fans of 80w each for 12 hours each day

E= 2 ×P×T

2×80w×12h

160÷1000kwh × 12h

1.92kwh

3) Energy consumed by electric tubes of 18w each of 6 hours in each day

E= 6 × p× t

6×18×6h

108÷1000w × 6h

0.648kwh

Total energy consumed by month of June (30 days )

(0.8+1.92+0.648)× 30kwh

6.568 × 30

197.04kwh

Electricity bill for the month of June Rs 197.04 × 3

Rs 591.12( approx)