1. Electricity consumed by a household using incandescent bulb is 1480 units costing Rs. 4.50 per unit. Given that compact fluorescent lights (CFL’s) consume four times less energy and last eight times longer than incandescent bulbs:
Answer the following questions:
(i) How many units will be consumed if all bulbs are changed to CFL’s?
(ii) What amount will be paid when incandescent bulbs are used?
(iii) What amount will be paid when CFL’s are used?
(iv) If one incandescent bulb lasts for 2 months, how long will a CFL last?
(v) What is the ratio of units consumed when a comparison is made with an incandescent bulb and a CFL is used? Is it in proportion to the cost?
(vi) What value is learnt from this?
Answers
Answer:
Step-by-step explanation:
Given
1. Electricity consumed by a household using incandescent bulb is 1480 units costing Rs. 4.50 per unit. Given that compact fluorescent lights
Now electricity consumed by a household using incandescent bulb is 1480 units.
The compact fluorescent lights consume four times less energy.
So now energy consumed by bulbs will be 1480 units.
Since all bulbs will be replaced by CFL bulbs, number of bulbs will be 1480/4 = 370 units.
1. 370 units will be consumed if all bulbs are changed to CFL.
2. Amount will be 1480 x 4.50 = Rs 6,660
3. Amount for CFL bulbs will be 370 x 4.50 = Rs 1665
4. CFL bulbs lasts for 8 x 2 = 16 months.
5. The ratio of units consumed will be 1480 : 370. No, Cost will be Incandescent bulbs are 4 times costlier than CFL bulbs. That is 1665 : 6660 = 1 : 4
6. From this we can analyse that it is best to use CFL bulbs and benefit cost wise and also lasts longer.