Question

Which one has consumed more energy when they worked continuously for 1 hour

a) An electric iron 0f 1000W
b) An electric lamp of 60W
c) A washing machine of 10400W
d) An electric hair dryer of 1500W​

Answer 1

Given

• Power of Electric iron = 1000 W = 1 kW
• Power of lamp = 60 W = 0.06 kW
• Power of a washing machine = 10400 W = 10.4 kW
• Power of a electric hair dryer = 1500 W = 1.5 kW
• Time = 1 hour

To Find

• Appliances that consumes the most energy Consumed

Solution

● Electrical Energy consumed is equal to the product of the power and the time

✭ Energy consumed by Iron :

→ E = Power × time

→ E = 1 × 1

→ E(ᵢᵣₒₙ) = 1 kWh

✭ Energy consumed by lamp :

→ E = Power × time

→ E = 0.06 × 1

→ E(ₗₐₘₚ) = 0.06 kWh

✭ Energy consumed by washing machine :

→ E = Power × time

→ E = 10.4 × 1

→ E(ₘₐ꜀ₕᵢₙₑ) = 10.4 kWh

✭ Energy consumed by hair dryer :

→ E = Power × time

→ E = 1.5 × 1

→ E(dᵣᵧₑᵣ) = 1.5 kWh

∴ The washing machine consumes the most energy

Answer 2

Given:-

$\bigstar$An electric iron of 1000 W

$\bigstar$An electric lamp of 60 W

$\bigstar$An washing machine of 10400 W

$\bigstar$An electric hair dryer of 1500 W

To Prove:-

$\bigstar$Which one has consumed more energy?....

Solution:-

$\bigstar$First convert W to K W..

An electric iron of 1000 W - 1 K W

An electric lamp of 60 W - 0.06 K W

An washing machine of 10400 W -10.4 KW

An electric hair dryer of 1500 W - 1.5 K W

$\bigstar$Formula being used for below cases:-

$\longrightarrow{ \underline{ \boxed{ \boxed{ \sf{energy = power \times time}}}}}$

First Case:

$\bigstar$An electric iron of 1000 W:-

$\longrightarrow \sf \: E \: = 1 \times 1 = 1 \: k Wh$

$\bigstar$The energy consumed by electric iron is 1 kWh

Second Case:-

$\bigstar$An electric lamp of 60 W:-

$\longrightarrow \sf \: E \: = 0.06 \times 1 = 0.06 \: k Wh$

$\bigstar$The energy consumed by electric lamp is 0.06 kWh

Third Case:-

$\bigstar$A washing machine of 10400 W

$\longrightarrow \sf \: E \: = 10.4 \times 1 = 10.4 \: k Wh$

$\bigstar$The energy consumed by washing machine is 10.4 kWh

Fourth Case:-

$\bigstar$An electric hair dryer of 1500 W

$\longrightarrow \sf \: E \: = 1.5 \times 1 = 1.5 \: k Wh$

$\bigstar$The energy consumed by electric hair dryer is 1.5 kWh

°Among this 4 case the washing machine has consumed more energy...