Question

State Joule’s law of heating. List two special characteristics of a heating element wire. An electronic iron consumed energy at the rate of 880 W when heating is at the maximum rate and 440 W when the heating is at the minimum rate. The applied voltage is 220 V. Calculate the current and resistance in each case

Answer 1

Answer:

pls see the attachment

Answer 2

Answer:

Joule's law of heating depicts that :

• The heat generated is directly proportional to the square of current.
• It is directly proportional to the resistance.
• It is directly proportional to the time.
• H = I^2 RT

Explanation:

P = VI

880W = 220 V × I

880/220 = I

I = 4A

V = IR

220 = 4 × R

220/4 = R

R = 55 Ohm

P = VI

440 = 220 × I

440/220 = I

I = 2 A

V = IR

220 = 2 ×R

220/2 = R

R = 110 Ohm