Ashish Kumar - let's Learn, implement then understand Maths and Physics

Our greatest fear should not be of failure but of succeeding at things in life that don’t really matter. – Francis Chan

# Lecture 9 Units and Measurement

Example 2.9 The resistance R = V/I where V = (100 ± 5)V and I = (10 ± 0.2)A. Find the percentage error in R.

Example 2.10 Two resistors of resistances R1 = 100±3 ohm and R2 = 200 ± 4 ohm are connected
(a) in series,
(b) in parallel.
Find the equivalent resistance of the
(a) series combination,
(b) parallel combination.
Use for (a) the relation R = R1 + R2 and for (b) \frac{1}{R} = \frac{1}{R_1} + \frac{1}{R_2} and \frac{\Delta R}{R`^{2}} = \frac{\Delta R_1}{{R_1}^2} + \frac{\Delta R_2}{{R_2}^2}