Copper and silicon is cooled from 300 K to 60 K, the specific resistance

Options

A. decrease in copper but increase in silicon
B. decrease in silicon but increase in copper
C. increase in both
D. decrease in both

Answer

A

Explanation

James final velocity `v_(f)`
`v_(f) = 40 + 25 xx (92)/(100) = 42.3`
`:. V_(x_(0)) = v_(f) cos 20 = 40 m//s`
Retardation, `a = (-600)/(1000) = -6`
`v_(x) = 0 rArr 40 - 6t = 0`
Final horizontal component `t = (20)/(3)`
`x = 40 xx (20)/(3) - (1)/(2) xx 6 xx ((20)/(3))^(2) = 133 m`