4th Street Bar Hive-Bar

Hive-Bar Powered by Hive beta-fdb5b5b

Community post

how an automatic fire alarm works

20170622_215910.jpg

The automatic fire alarm system uses the fact that different solids expand by different amounts on heating . The alarm contains two metal stripes , one of iron and the other of brass , firmly bolted together . Brass expands more than iron on heating . Therefore , when this bimetallic strip gets heated because of fire , it bends on the side of iron . As it bends , the circuit of the electric bell is completed . The starts ringing to give the alarm . As the fire is put out , the strip gets cooled and straightens again . This causes the circuit to break , thus switching off the alarm .

please feel free to comment/resteem/follow @dhingrapranay15 for posts on lifestyle and good passage of time . bye have a nice day .

13 upvotes $0.33

Replies (2)

Review before signing

Posting as . Signing with . Keychain permission: Posting. Hive Keychain will ask you to approve this action next.


  
Technical details

Operation fingerprint: