[" 24.The resistivity does not "],[" change if: " "]

Two materials have the value of alpha_(1) and alpha_(2) as 6 xx 10^(-4) (""^(@) C )^(-1) and - 5 xx 10^(-4) (""^(@) C )^(-1) respectively. The resistivity of the first material rho_(20) = 2 xx 20^(-8) Omega. A new material is made by combining the above two materials. the resistivity does not change with temperature . The resistivity rho_(20) of the second material is .... Considering the reference temperature as 20^(@) C assume that the resistivity of the new material is equal to the sum of the resistivity of its component materials.

From rated value of power and potential difference the resistance of the appliance can be found by the formula R=(V_(rated)^2)/(P_(rated)) . This resistance does not change if the same appliance is used across different potential difference. But the power of appliance will change. Is this statement true.

A carbon and an aluminium wire are connected in series. If the combination has equivalent resistance of (90 Omega) at ( 0^@C ), the value of the resistance of each wire at (0^@C) so that the resistance of combination does not change with temperature is

The temperature coefficient of resistance of tungsten is 4.5 xx 10^(-3) ""^(@)C^(-1) and that of germanium is - 5 xx 10^(-2)""^(@)C^(-1) . A tungsten wire of resistance 100 Omega is connected in series with a germanium wire of resistance R. The value of R for which the resistance of combination does not change with temperature is .

A carbon and an aluminium wire are connected in series . If the combination has equivalent resistance of 90 Omega at 0°C, the value of the resistance of each wire at 0°C so that the resistance of combination does not change with temperature is ( alpha_c=-0.5×10^(-3)°C^(-1) and alpha_Al=-4×10^(-3)°C^(-1) )

State whether the resistivity of a wire changes with the change in the thickness of the wire.

As the temperature of a conductor increases,its resistivity and conductivity change.the ratio of resistivity to conductivity

As the temperature of a conductor increases,its resistivity and conductivity change.the ratio of resistivity to conductivity