If you were to plot the voltage vs. the current for a given circuit, what would you expect the
slope of the line to be? If now the resistance of the circuit were a function of temperature would you still expect to see a straight line when plotting V vs. I, if the temperature was allowed to vary?

Explanation:

For a circuit containing ohmic conductors , the slope represents resistance of the circuit . It is so because according to ohm's law , ratio of voltage and current is constant or

V / I = R ( constant ) , V is voltage , I is current and R is resistance.

V = R I

It is similar to equation of a line in coordinate geometry

y = m x , m is slope of straight line.

In case of circuit containing non ohmic conductors , line will not be a straight line . It will be an upward sloping curve . It happens because of varying resistance at all value of potential . The slope at each point on the curve gives the value of instantaneous resistance .

When temperature changes , resistance too changes so even in case of ohmic conductors , slope changes as temperature changes . For a particular temperature , graph will be straight line.

d eras and periods

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27