Question

In the two 'set-ups' X and Y, shown on the next page, the wires AB and PQR
are made of the same material and have equal thickness! The length of the
wire AB, (in the set-up 'X') is equal to the diameter (= PR) of the semi-circle,
formed by the wire PQR, (in the set-up Y'). Pins, P1 and P2, are attached, to
wires AB and PQR respectively, with the help of wax. Which of the two pins,
P1 or P2, will fall off later? Give reason for your answer.​

Answer 1

Explanation:

We know that R=

A

ρ×l

Given the material of both wires A and B is same and their lengths are also given to be same. ρandl are constant.

So, we have the relation:

R

B

R

A

=

A

A

A

B

=

1

4

So,

A

B

A

A

=

4

1