The magnetic susceptibility of a paramagnetic substance at `-73^(@)` is `0.0050`. Calculate magnetic susceptibility at `-173^(@)`C.

Options

A. `0.010`
B. `0.0025`
C. `0.0020`
D. `0.0030`

Answer

A

Explanation

According to Curie.s law, `chi_(m) = (mu_(0) C)/( T) , mu_(0) C` is constant
`therefore chi_(m) prop (1)/(T)`.
`therefore (chi_(m_(2) ) )/( chi_(m_(1) ) )= (T_1)/( T_2)`
`therefore (chi_(m_2) ) /( 0.005) = (273 - 73)/( 273-173) = (200)/( 100)`
`therefore chi_(m_2) = 2 xx 0.005 therefore chi_(m_2) = 0.010`