" 13.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.

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

A carbon and an aluminium wire are connected in series. If the combination has resistance of 30Omega at 30^@C , what is the resistance of each wire at 0^@C so that resistance of the combination does not change with temperature. (a_c=-0.5 times 10^-3//^@C,a_A=4 times 10^-3//^@C )

A carbon and an aluminimum wire are connected in series.If the combination has resistance of 27 ohm at 0^(@)C ,what is the resistance of each wire at 0^(@)C so that the resistance of the combination does not change with temperature ? [alpha_(C ) = -0.5 xx 10^(-3)(.^@C)^(-1) and alpha_(A) = 4 xx 10^(-3)(.^@C)^-1] .

A carbon and an aluminium wire are connected in series. If the combination has resistance of 30Omega at 30^@C , what is the resistance of each wire at 0^@C so that resistance of the combination does not change with temperature. (a_c=-0.5 times 10^-3//^@C,a_A=4 times 10^-3//^@C )

The mass of a body does not change with change in _____.

The mass of a body does not change with change in _____.