True or False: Flat straight bi-metals produce thermostats with slow opening contacts.

The statement is true because flat straight bi-metals are designed to have specific thermal properties that affect how quickly they respond to temperature changes. When heat is applied to a flat straight bi-metal, the two different metals expand at different rates due to their unique coefficients of thermal expansion. This differential expansion causes the bi-metal to bend and ultimately close or open the contacts in a thermostat.

In the case of flat straight bi-metals, their design contributes to a slower response time in the opening and closing of contacts compared to other types of bi-metal configurations. This slow opening characteristic is particularly useful in applications where gradual temperature changes need to be managed to prevent rapid cycling of the heating or cooling systems, which can lead to inefficiency or wear on the equipment.

Other options imply different circumstances affecting the response of thermostats, such as the materials used or temperature ranges, but flat straight bi-metals specifically are known for their slow opening characteristics regardless of these factors.