wiz-icon
MyQuestionIcon
MyQuestionIcon
16
You visited us 16 times! Enjoying our articles? Unlock Full Access!
Question

A toaster produces more heat than a light bulb when connected in parallel to a 220V mains. Which one has a greater resistance. Please give detailed explanation.

Open in App
Solution

3 answers · Physics

Best Answer
Electrical heating comes from the power dissipated in a resistor, given by P = I^2 * R (where P=power, I=current, R=resistance). Also, V=IR; this can be rearranged to state I=V/R. This can be substituted into the equation for power to state:
P = I^2 * R
=(V/R)^2 * R
=V^2/R
Power is inversely proportional to resistance at constant voltage. Therefore, for circuits connected to a constant voltage source (the 220 volt mains), the one with the lowest resistance will have the highest heat. If the toaster gets hotter, it has lower resistance.

flag
Suggest Corrections
thumbs-up
6
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Intrinsic Property_Tackle
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon