Question

An electric motor takes 5 A from a 220 V line. Determine the power of the motor and the enrgy consumed in 2 hours.​

Answer 1

✬ Power = 1100 W ✬

✬ Energy = 7.92 × 10⁶ J ✬

Explanation:

Given:

• Current is 5 ampere.
• Voltage is 220 volts.
• Time is 2 hours.

To Find:

• What will the power of the motor and energy consumption ?

Formula to be used:

• P = V × I
• Energy = Power × time

Solution: Here we have

• I = 5 A
• V = 220 V
• T = 2 h
• P = ?
• E = ?

Put the values on the first formula

$\implies{\rm }$ P = V × I

$\implies{\rm }$ P = 220 × 5

$\implies{\rm }$ P = 1100 W

So the power of motor is 1100 watts.

Changing the time into seconds

• 1 hour = 3600 s
• 2 hours = 7200 s

Now using the second formula

$\implies{\rm }$ E = P × T

$\implies{\rm }$ E = 1100 × 7200

$\implies{\rm }$ E = 7920000 J

$\implies{\rm }$ E = 792 × 10⁴

$\implies{\rm }$ E = 7.92 × 100 × 10⁴

$\implies{\rm }$ E = 7.92 × 10² × 10⁴

$\implies{\rm }$ E = 7.92 × 10⁶ J

Hence , energy consumed by the motor is 7.92 × 10⁶ J.

Answer 2

✬ Power = 1100 W ✬

✬ Energy = 7.92 × 10⁶ J ✬

Explanation:

Given:

Current is 5 ampere.

Voltage is 220 volts.

Time is 2 hours.

To Find:

What will the power of the motor and energy consumption ?

Formula to be used:

P = V × I

Energy = Power × time

Solution: Here we have

I = 5 A

V = 220 V

T = 2 h

P = ?

E = ?

Put the values on the first formula

\implies{\rm }⟹ P = V × I

\implies{\rm }⟹ P = 220 × 5

\implies{\rm }⟹ P = 1100 W

So the power of motor is 1100 watts.

Changing the time into seconds

1 hour = 3600 s

2 hours = 7200 s

Now using the second formula

\implies{\rm }⟹ E = P × T

\implies{\rm }⟹ E = 1100 × 7200

\implies{\rm }⟹ E = 7920000 J

\implies{\rm }⟹ E = 792 × 10⁴

\implies{\rm }⟹ E = 7.92 × 100 × 10⁴

\implies{\rm }⟹ E = 7.92 × 10² × 10⁴

\implies{\rm }⟹ E = 7.92 × 10⁶ J

Hence , energy consumed by the motor is 7.92 × 10⁶ J.