Remarks (1)The current thru a resistor is a the voltage across 止t (2 )A resistor satisfying this law is said to be linear (3)The current and voltage are measured as in Fig.5-4 The current thru a voltmeter is usually assumed to be negligible compares with that thru R R Figure 5.4 Measurement of the current I through a resistor R, and of the voltage v across it. A circle marked I represents an ammeter, and a circle marked v,a voltmeter