Question

an electric bulb rated at 100W is connected to the mains supply. Find the amount of electrical energy consumed by the bulb in 30 days if the bulb is switched on for 8 hours daily​

Answer 1

Given

An electric bulb rated at 100 W is connected to the mains supply

Find the amount of electrical energy consumed by the bulb in 30 days if the bulb is switched on for 8 hours daily​

To Find

Electrical Energy

Solution

We know that

→ E = P × t

Here

• E = Electrical Energy
• P = Power
• t = Time

According to the question

We are asked to find electrical energy

Therefore

We must find "E"

Given that

An electric bulb rated at 100 W is connected to the mains supply

Find the amount of electrical energy consumed by the bulb in 30 days if the bulb is switched on for 8 hours daily​

Hence

• P = 100 W
• t = 8 × 30 h = 240 h

Substituting the values

We get

→ E = 100 × 240 W h

→ E = 24000 W h

Therefore

→ E = 24 kW h

Hence

Electrical Energy = 24 kW h

Answer 2

Answer:

Given :-

• An electric bulb rated at 100 W is connected to the mains supply.
• A bulb in 30 days if the bulb is switched on for 8 hours.

To Find :-

• What is the amount of electrical energy consumed by the bulb.

Formula Used :-

$\boxed{\bold{\small{Electrical\: energy\: =\: P\: \times t}}}$

where,

• P = Power
• t = Time

Solution :-

Given :

• Power = 100 W
• Time = 30 d × 8 h = 240 h

According to the question by using the formula we get,

↦ Electrical energy = 100 × 240

↦ Electrical energy = 24000

We know that,

1 kWh = 1000 Watt-Hour

Then, 24000 = $\dfrac{24000}{1000}$

↦ Electrical energy = $\dfrac{\cancel{24000}}{\cancel{1000}}$

➠ Electrical energy = 24 Watt-Hour

$\therefore$ The amount of electrical energy consumed by the bulb is 24 Watt-Hour .