Question

an electrical appliance has a rating 100W and 120V, the resistance of element of appliance when in use is ?

Answer 1

Answer :-

144 Ω is the resistance.

Explanation :-

Given :

Power (P) = 100 W

Voltage (V) = 102 V

To find :

Resistance (R)

Solution :

P = VI

100 = 120 × I

I = 100/120

I = 10/12

I = 5/6 A

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V = IR (Ohm's Law)

120 = 5/6 × R

120 × 6/5 = R

24 × 6 = R

R = 144 Ω

Answer 2

Given:-

• Power of Appliance ,P = 100W
• Potential Difference ,V = 120v

To Find:-

• Resistance of the appliance ,R

Solution:-

According to the Question

It is given that electrical appliance has a rating 100W and 120V. we have to calculate the resistance of appliance .

As we know the relationship between , Power , Potential Difference & Resistance.

• P = V²/R

where,

• P denote Power
• V denote Potential Difference
• R denote Resistance

Substitute the value we get

→ 100 = 120²/R

→ 100 = 14400/R

→ 100 × R = 14400

→ R = 14400/100

→ R = 144Ω

• Hence, the resistance of the appliance when it is in use is 144 ohm.