Question

a wire of length 10 m has a resistance 100 ohm.if wire is stretched to increase its lenght three times what will be its new resistance?​

Answer 1

Answer:

we know that length is directly proportional to the resistance of the conductor

so, r1/r2 = l1/l2

from the given question, r1= 100ohms, l1= 10m.

according to the problem, length is increased 3times

so, l2 = 30m

then,

r1/r2=l1/l2

100/x=10/30

10x = 100×30

x = 100× 3

x ( resistance of the new wire ) = 300 ohms