Safety In Numbers
A fuse is a safety device used to protect an electrical circuit from the effects of excessive current. It consists of a thin metal wire with small resistance and low melting point. When an electrical equipment becomes faulty (allowing an excess electric current to flow through the circuit), the wire inside the fuse melts which breaks the flow of the current. The rated current
is the maximum current that a fuse can conduct without interrupting the circuit. Consider two identical fuses with
connected in parallel as shown in the figure at the top.
What is the maximum current in Amperes that can flow through the circuit?
The answer is 4.0.
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5 solutions
Discussions for this problem are now closed
considering both fuses were identical they would have the same electrical resistance, being in paralel means we have to apply 1/R=1/R 1+1/R 2....1/R_n.
Following the explanation electricity in a paralel circuit always has a greater current in the branch with less resistance thus having both branches the same resistance the electrical current would divide equitatively among both branches, thus, the total current would be divided by 2, and each fuse only allows 2 Amps therefore rearanging the equation we find that 2*2 is 4Amps