Sheet 1
Define the following: Error, Accuracy, and Precision.
1-The current through a resistor is 1.5 A, but measurement yields a value of 1.46 A. compute the absolute
error and percentage of error of the measurement.
2-The value of a resistor is 2 KΩ; however, measurement yields a value of 1.93 KΩ. Compute the relative
and percentage accuracy of the measurement.
3-If the average of a set of voltage readings is 30.15v. compute the precision of one of the readings that was
equal to 29.9 v
4- The output voltage of an amplifier was measured by six different students using the same oscilloscope with
the following results 20.20 V, 19.90 V, 20.05 V, 20.10 V, 19.85 V, 20.00 V Which is the most precise
measurement?
5-Two resistors were selected from a supply of 2200±10% resistors.
(a) Assume both resistors are 2200± 0% Ω, compute the expected resistance of the parallel combination
(b) Assume both resistors are 2200+10% Ω, compute the expected resistance of the parallel
combination.what is the percent error when compared to a?
(c) Assume both resistors are 2200-10% Ω, compute the expected resistance of the parallel
combination.what is the percent error when compared to a?
6-Three resistors, to be connected in series, were selected from a supply of 470.000±10% resistors.
(d) If all three resistors are 470.000± 0% Ω, what is the expected value of the series combination?
(e) If all three resistors are 470.000+10% Ω, what is the expected value of combination? what is the percent
error when compared to results in part a?
(f) If all three resistors are 470.000-10% Ω, what is the expected value of combination? what is the percent
error when compared to results in part a?
7- A 160 ± 10% pF capacitor, an inductor of 160±10% µH, and a resistor of 1200± 10%Ω are connected in
series
1
(a) If all three components are ±0%, and fr = 2𝜋𝜋 /√𝐿𝐿𝐿𝐿, Compute the expected resonant frequency of the
combination
(b) If all three components are +10%, Compute the expected resonant frequency of the combination and
the percent error when compared to the results of part a.
(c) If all three components are -10%, Compute the expected resonant frequency of the combination and
the percent error when compared to results of part a
8- A 150 ± 10%Ω resistor is connected to terminals of a power supply operating at 200± 0 Vdc. What range
of the current would flow? If the resistor varies over the range of ±10% of its expected value? what is the
range of error in the current?
9- The diameter of a copper conductor varies over its length as shown in the following table.
(a) Calculate the precision of each measurement
(b) Calculate the average precision
Reading number
1
2
3
4
5
6
Diameter (mm)
2.21
2.18
2.20
2.21
2.17
2.19
10- A voltmeter is accurate to 98% of its full-scale reading.
(a) If a voltmeter reads 175 V on 300-V range. What is the absolute error of reading?
(b) What is the percentage of error of reading in part a?
11- It is desired to determine a voltage to within one part in 300. What accuracy of the meter is required?
12- Eight resistors having a color-coded value of 5.6KΩ were measured and found to have the following
values determine the standard deviation of the batch.
Resistor number
1
2
3
4
5
6
7
8
Value (KΩ)
5.75
5.60
5.65
5.50
5.70
5.55
5.80
5.55
13- A circuit was tuned for resonance by eight different students, and the following values for the resonant
frequency of the circuit were recorded. Compute the arithmetic mean, the average deviation, and the standard
deviation for reading.
Reading NO.
1
2
3
4
5
6
7
8
Resonance frequency (kHz)
532
548
543
535
546
531
543
536