A 230 V supply is joined to a 92 Ω resistor for two minutes.
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A supply is joined to a resistor for two minutes. What current flows, and how much heat is produced?
Need a reminder? The key ideaShow
Joule's law: . Power , in watts. A fuse, in the live wire, melts when the current is too large.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Current. .
Step 2. Heat. .
Answer: , and ().
Check. .
Discussion (0)
Log in to join the discussion.
Loading…