Question

18. A 100 W electrical bulb is lighted for 2 hours
every day and five 40 W tubes are lighted for
4 hours every day. Calculate (a) the energy
consumed for 60 days and (b) cost of electricity
consumed at the rate of 1.50 per kWh.​

Answer 1

Answer:

Given-;

100 W electrical bulb is lighted for 2 hours

100 W electrical bulb is lighted for 2 hoursevery day.

five 40 W tubes are lighted for 4 hours every day.

Calculate-;

I) the energy consumed for 60 days.

II) cost of electricity consumed at the rate of 1.50 per kWh

____________________

I) Energy consumed by a 100 W bulb each day is,

E = 100 W × 2h

= 200 Wh

= 0.2 kWh

Energy consumed by five 40 W tubes each day,

E = 5×40 W × 4 h

= 800 Wh

= 0.8 kWh

Therefore,

total energy consumed each day

= 0.2+0.8 = 1.0 kWh

total energy consumed in 60 day

= 1.0×60 = 60kWh✓

II) cost of 1 kWh electricity = Rs 1.50

So, cost of 60kWh = 1.50×60

Rs = 90 ✓