Question

A small heater can be created by connecting a 10-ohm resistor across a 24-volt battery. Assume the battery is an ideal 24-volt potential source, and that any wires used to connect the battery to the resistor are also ideal and have negligible resistance.

Part A) Calculate the power dissipated as heat by this circuit. (Answer in Watts)

Part B) 4.18 Joules of energy are required raise 1.0 mL of water by 1∘ C. We wish to modify our 24-volt heater to heat 355 mL (12 fluid ounces) of water at a rate of 0.1∘ C per second. Assume that the water is in an insulated cup so that no heat is lost to the surrounding environment. What resistor would we need to use in place of the original to achieve this heating rate? (Answer in ohms).

Answer 1