Q. A certain brand of hotdog cooker works by applying a potential difference of 142 V across opposite ends of a hot dog and allowing it to cook by means of the thermal energy produced. The current is 13.4 A, and the energy required to cook one hot dog is 60.7 kJ. If the rate at which energy is supplied is unchanged, how long (in s) will it take to cook three hot dogs simultaneously?
Q. A copper wire of cross-sectional area 2.40 × 10-6 m2 and length 3.40 m has a current of 2.00 A uniformly distributed across that area.
(a) What is the magnitude of the electric field (in N/C or V/m) along the wire?
(b) How much electrical energy is transferred to thermal energy in 35.0 min?