The resistance Rt of a conductor varies with temperature t as shown in the figure. If the variation is represented by , then
(1) α and β are both negative
(2) α and β are both positive
(3) α is positive and β is negative
(4) α is negative and β are positive
(3) Since the value of R continuously increases, both α and β must be positive.
Actually the components of the given equation are as follows
It α is positive, β is negative, the component will be shown in the following graph.
In this case, the value of R will not increase continuously. Hence the correct option is (3).