# Fusing factor equations

1. Apr 8, 2009

### Ga San Wu

hi all,

ive been doing an experiment to do with fusing factors and unfortunately i didnt read
my experiment coursework sheet properly and have only recorded the current going
through a wire at a certain voltage. the results have then been used to work out the resistance,
i was wondering whether there was an equation to work out the fusing
factor with only the voltage, current, resistance and length

for example,
3cm length constantan wire
0.2v across the wire
the resistance is therefore 0.07

i have read an old question that is exactly what i am doing but i am still rather confused.

Julien

2. Apr 8, 2009

### Ga San Wu

so far i have come up with one equation that seems
to answer most of my problems.

the equation is as follows (lets hope i can use this symbol thing properly!)

$$\\I_f = \\C \\d^\frac{3}{2}$$

(Hurrah the symbols worked!)
$$\\I_f$$ is the fusing current

$$\\C$$ is Preece's Constant ( it depends on which material you use)

$$\\d$$ is the diameter but be careful it has to be in inches

Last edited: Apr 8, 2009