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which causes an air conditioner to turn on?
house-temperature decreases cause the bimetallic coil to expand or contract.
house-temperature decreases cause the bimetallic coil to return to normal.
house-temperature increases cause the bimetallic coil to expand or contract.
house-temperature increases cause the bimetallic coil to return to normal.

House temperature increases cause the bi metallic strip to expand or contract.

Explanation:

A bimetallic strip is used in the heat dependent switches like the one used in air conditioners. Once the temperature changes, the lengths of the two types of metal making the strip change in different ratios thus bending to make the contact thus turning the air conditioner on.

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force