A Bimetallic Coil is formed from two pieces of different metals stuck together lengthwise.
Option A
Step-by-step explanation:
It is formed with two metal pieces that are stuck together in proper length. It is also called bimetallic strip which is mainly used for converting temperature into mechanical displacement. This coil or strip is consist of two different metal that are "steel and copper" or "steel and brass". With "riveting", welding and brazing the strip in the metals are joined length wise together. The displacement in the sideways of strips is more than smaller length ways expansion. The effect produced is used is basically used in mechanical and electrical devices.