ICSE Class 10 Answered
The working of the fuse depends on the heating effect of the current. In normal operating condition,
the normal current passes through the fuse. The heat develops in the fuse element because of the normal current
and this heat is dissipated by the help of the surrounding air. Thus, the temperature of the fuse is kept below the melting point.
When the fault occurs the short circuit current passes through the fuse element. The magnitude of the current
is much high as compared to the normal current. The short circuit current generates excessive heat in the fuse element.
Thereby, the element becomes melts and break. In this way . fuse protects the machine or apparatus from short circuit or overload current.