Question

Lengths of two metal bars 'A' and 'B' are 8cm and 12cm respectively. If they show same difference in length at all temperature, their superficial expansivities are in the ratio

4:9
3:2
2:3
9:4

Answer 1

Explanation:

2:3 is the right one.i hope its correct

Answer 2

Answer:

3:2

Explanation:

La=8cm

Lb=12cm

here,

change in length of A=change in length of B.

i.e.

del La=del Lb

By formula we know...

Alpha(a) La del theta=Alpha(b) Lb del theta

Beta(a)/2.8=beta(b)/2.12

Upon solving

required ration=3:2