Question

An electric travel blanket uses a car's 12V supply. The current is 3A.

a) What is the power of the blanket?

b) How much energy does it transfer if it is switched on for 10 minutes?

Answer 1

For electrical devices . . .

           Power dissipated = (voltage) x (current) =

                                             (12 V)  x  (3.0 A) = 36 watts .

1 watt means 1 joule per second

           (36 joule/sec) x (60 sec/min) x (10 min)  =  21,600 joules