Question

The Young's modulus of a wire of length
L and radius r is Y . If the length and
radius are reduced toL/3 and r/3
respectively, then its Young's modulus
will be
A Y/2, B Y, C 2Y, D 4Y​

Answer 1

Answer:

first of all its physics question

Explanation:

now we know that

R(resistance) is directly proportional to the length

R is inversely proportional to the cross sectional area of the wire

R is is directly proportional to the resistivity(roh)

→ R= ρ× L/A

so if length is reduced then resistance also decreases!

similarly radius is used to measure area

therefore if radius decreases resistance increases

so r/3

area = π r²

therefore its like 3R × r/3 =.Y

ans. = B )

Y