Question

If an electric bulb has a rating 200W-220V and if it is used for 6 hours daily for 15 days, calculate the cost of using the bulbs at 50 paise per unit.

Answer 1

Answer:

Total cost of using bulb = 9 Rs

Explanation :

Given :

֎ Rating of electric bulb = 200 W - 220 V

֎ Power of electric bulb P = 200 W

֎ Time for which bulb is daily used, t = 6 hrs

֎ Number of days for which bulb is used = 15 days

֎ Rate of cost per kWh energy = 50 Paise

To find :

Cost of using the bulb

Formula will be used :

֎ E = P× t

Here, E is the electrical energy in Watt - hour unit ,

P is the Power in Watt unit

and t is the time in hours

Solution :

By using formula →

$\sf \: E = P× t \\ \: \: \: \: \: \sf = 200 \times 6 \\ \sf \: \: \: \: \: = 1200 \: \: Wh \:$

Again, we know that,

→ 1 kWh = 1000 Wh

therefore,

$\sf\:E = 1200 \: \: Wh \\ \sf \: \: \: \: = \sf\: \frac{1200}{1000} \: KWh \\ \sf \: \: \: \: = 1.2 \: \: KWh \:$

Calculating total energy consumed by bulb in 15 days

Total Energy consumed = 15 × 1.2 KWh

So , total energy consumed = 18 KWh

Now,

Calculating Cost of using bulb at 50 paise per KWh

⇨ Total cost of using bulb = 50× 18 paise

= 900 Paise

Converting into Rupees,

Total cost of using bulb = 900/100 Rs

= 9 Rs

$\red{ \boxed{ \green {\sf \: so \: total \: cost \: is = \: 9 \: \: Rs}}}$

Answer 2

Answer:use the formula

Explanation: