Question

Disha was given two thin wires A and B in science laboratory. The teacher asked her to find out which wire was “fuse wire” and which one was “nichrome wire”. Disha was given batteries of 3 V and 12 V and some connecting wires. The teachers also advised her to switch off fan while performing the activities and take necessary precautions to avoid burns. Disha performed the activities for testing and concluded that wire A is nichrome wire, whereas wire B is fuse wire. 

On the basis of above information, answer the following questions 

(i) Describe the activity which Disha performed to conclude that wire A is nichrome wire. 

(ii) Describe the activity which Disha performed to conclude that wire B is fuse wire.

Answer 1

i) • Disha connected wire A with both the batteries. 

• When wire A was connected with 3v battery, Disha found that the wire started heating. 

• When the wire A was connected with 12V battery, she found that the wire is emitting a large amount of heat. 

• Thus, she concluded that wire A is a nichrome wire as nichrome wire has a very large resistance and it produces a large amount of heat. 

ii) • Disha connected wire B with both the batteries. 

• When wire B was connected with 3v battery, did not find anything. 

• When the wire B was connected with 12V battery, she found that the wire has started melting and. 

• Thus, she concluded that wire B is a fuse wire as fuse wire has a very low melting point and it melts as a large amount of current is made to pass through it.