2007-03-06 14:26:52 · 5 answers · asked by theranikal 2 in Science & Mathematics ➔ Earth Sciences & Geology
Temperature will effect the resistivity of the metals. By measuring the difference in resistance between the the two metals you can determine the temperature. The thermostat is set to cut out when a certain resistance is met.
2007-03-06 14:41:57 · answer #1 · answered by Professor Kitty 6 · 0⤊ 1⤋
Each of the metals selected expands during heating at a different rate than the other. Therefore when the heater being controlled is on, one of them expands in a direction which makes (or breaks) the circuit and turns off the heater when the thermostat setpoint is reached. The opposite is true if the bimetallic strip controls a cooling function.
2007-03-06 14:31:46 · answer #2 · answered by David A 5 · 2⤊ 0⤋
Prniciple: differential expansion of different metals
two metals, one have higher expansion with heat and another one less expansion with heat is joined. this is called bimetallic strip. when current passes through this, due to electrical resistant there will be a temperature prodcution in the metal. at that temperature, each will expand depending upon its expanding property (one highly, other slowly).
due to this, the bimetallic strip will lean towards the metal which is expanding more. due to this leaning away (mechanism is like that ), the current flow is cut off. once the current cut off occurs the temperature slowly decreases and consequently, the metal will attain its original shape i.e, straight. now again the current flow occurs and hence heat again produced.
thus constant temperature is maintained
mani, dept of soil,
tnau
2007-03-06 14:58:20 · answer #3 · answered by malarmaniyan 2 · 1⤊ 1⤋
A bimetettalic strip expands differentlyand can be used as a thermometer.and can be so arranged sothat it can break orconect acircuitamd thus can beused as a thermostat
2007-03-06 15:04:08 · answer #4 · answered by vittalmurthy k 1 · 1⤊ 0⤋
by the difference in electric potential of different metallic strips.
2007-03-06 15:07:46 · answer #5 · answered by NQS 5 · 0⤊ 1⤋