What happens to a bimetallic strip when cooled?

When this bimetallic strip is heated, the brass expands more than the steel and the strip curves with the brass on the outside. If the strip is cooled, it curves with the steel on the outside. Bimetallic strips are used as switches in thermostats.

Why does a bimetallic strip bend when cooled?

Brass and Iron together form the bimetallic strip. The rate of expansion and contraction of brass is more when compared to Iron, that is, brass expands more than Iron when heated and contracts faster than iron when cooled. As a result, the bimetallic strip bends with the change in temperature.

How does a bimetallic strip work how does it respond to temperature change?

A bimetallic strip is made of two different kinds of metals that are laminated into one strip. Each metal responds to heat and cold by expanding a specific amount based on the change in temperature. When heat is applied to the coiled bimetallic strip, it expands and uncoils.

What happens when a bimetallic strip is heated?

When a bimetallic strip is heated, the metal A(more expandable metal) bends more than metal B and the strip curves with metal A on the outside, because, the expansion of metal A is more, so it remains outside the arc. And if the strip is cooled, metal B will be on the outside.

How does a bimetal strip work?

The bimetallic strip consists of two thin strips of different metals, each having different coefficients of thermal expansion. When the temperature decreases, the strip bends in the direction of metal having a higher temperature coefficient. The deflection of the strip indicates the temperature variation.

What is meant by bimetal strip?

bimetallic strip in British English noun. a strip consisting of two metals of different coefficients of expansion welded together so that it buckles on heating: used in thermostats, etc. Collins English Dictionary.

Why do metals bend when heated?

Once exposed to heat these molecules begin to vibrate and move around faster. This makes the molecules spread out and take up more space. As a result a material expands slightly when it gets hot. On the other hand, when a material is cold, molecules move less, which makes them take up less space.

How are bimetallic strips useful?

Bimetal strips are used in miniature circuit breakers to protect circuits from excess current. A coil of wire is used to heat a bimetal strip, which bends and operates a linkage that unlatches a spring-operated contact. This interrupts the circuit and can be reset when the bimetal strip has cooled down.

How does a bimetal strip operate?

It is simply two strips of different metals bonded together and held at one end. When heated, the two strips expand at different rates, resulting in a bending effect that is used to measure…

What happens when brass is cooled?

However, since brass expands (or contracts) more than iron when its temperature is raised (or cooled), the bimetallic strip will bend one way or another depending on the temperature being above or below room temperature.

How can a bimetallic strip be used to regulate temperature?

Bimetallic strips are used in thermostats for measuring and controlling temperature. The strip is connected to a switch and as the temperature changes the strip flexes and opens or closes a contact. They are also used in ovens for measuring temperature.

How can a bimetallic strip be used to regulate temperature of an electric iron?

A bimetallic strip controls the thermostat. This consists of a strip of brass in contact with a strip of iron. When the temperature is lower than normal room temperature, the length of the brass will be less than the length of the iron, and so the bimetallic strip will become “U-shaped” with the brass on the topside.