Question

Exercise 1.Suppose the color code on a resistor is yellow, violet, orange and gold. What is its resistance and what is the uncertainty of this resistance?

Exercise 2.Suppose you purchase a nominally 100 Ω resistor from a manufacturer. It has a silver band on it which signifies a 10% tolerance. What does this mean?

Exercise 3.A piece of wire of resistance? is cut into 5 equal lengths.These parts are connected in parallel. How does the joint resistance of the parallel combination compare with the original resistance of the single wire?

Answer 1

1.

According to, Electronic resistor color code sequence;

Black (0); Brown (1) ;Red (2) ; Orange (3) ; Yellow (4) ;Green (5); Blue (6); Violet(7) ;Grey(8) ;White (9)

The resistance is

Uncertainty of this resistance for gold is %

2.

10% tolerance means the value of resistance can vary up over time, up to 10 percent from its manufacturing value

That is 10% of 100 Ω is 10 Ω

Maximum value : 100 + 10 = 110  Ω

Minimum value : 100 - 10 = 90  Ω

3.

New Resistance will be,

Since 'n' equal resistances are connected in parallel :

For 5 resistances of R/5 are connected in parallel ;