Q23 of 238 Page 114

An electric iron is rated at 230 V, 750 W. Calculate

(i) the maximum current, and


(ii) the number of units of electricity it would use in 30 minutes.

(a) (i) the max. current, I= PV

So, 3.260A is the max current.


(ii) the number of units of electricity it would use in 30 minute is E= P*t


So, 0.75KW*0.5h= o.375KWh.


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