11.11.1999
Electronic Inst.
And Meas.
i-) 22 ii-) 245. iii-) 4.32 iv-)
256.322
b- ) Find the arithmetic mean
of the following data:
12.2, 5,
8.5, 14.32, 7.5,
6.5, 6.5, 5.5
c- ) Find the median of the
following data
5, 6,
4, 3, 2, 9, 7
d- ) Find the mode of the
following data
5, 6,
4, 3, 4, 2, 4,
7, 2, 9, 4
e- ) An
amplifier has an output signal of 3.6 Vrms when a sine wave input signal of 0.1
Vrms is present. State its gain in decibels.
a-
) Explain the function of the shunting resistor across
the meter movement.
b-
) Explain the function of the diode D2.
c-
) Calculate the values of series resistor R1,
R2, and R3 if the required meter ranges are 10
V. 50 V, and 100 V, respectively.
d-
) Determine the ohm-per-volt rating of this ac
voltmeter.
Dr.A.N.Yazıcı
16.12.1999
b-) The
quality factor Q of this circuit is determined as Q=³10. Reduce the
expression of Rx and Lx to the their simplest form using
the expression of Q.
c-)
Discuss how can you measure the unknown value of applied frequency (w or f) using this
circuit.
2. Firstly
draw the simple circuit diagram of a laboratory-type Cathode Ray Oscilloscope
(CRO) and then explain its function and describe its operational principle.
b-) An
average responding electronic ac voltmeter with an rms-calibrated scale is used
to measure the following nonsinusoidal voltage waveforms. The symmetrical
square and triangular wave voltages with an amplitude of 10 Volt. Calculate the
form factors (k) of both waveforms.
c-)
Calculate the percentage error indicated by the ac voltmeter for each of the
voltages cited.
(Hint : Percentage Error = %)
Dr.A.N.Yazıcı
19.01.2000
EP 485
Elec.Inst.and Meas.
Final
Exam (Time Duration : 100 Mins.)
1. a-) The
following prices are found for a certain brand of canned peas over a period of
six weeks : $1.96, $2.05, $1.75, $1.94, $2.25, $2.10. Calculate both the
arithmetic mean and the harmonic mean.
b-) Find the mean and standard deviation of the following set of weight measurements :
1.6 1.45 1.4 1.5 1.6
1.4 1.5 1.6 1.55 1.4
c-) Calculate the standard error of the mean for the sample in 1.b, and report it in the standard manner.
2. a-) Design an electrical circuit and then
obtain necessary equation to measure
the unknown impedance values.
b-) Determine the unknown component
values
(RX and LX) in the given
circuit in Fig.1.
3.
a-) A coil with a resistance of 10 W is
connected
in the “direct – measurement”
mode in
Q-meter. Resonance occurs when
the
oscillator frequency is 1.0 MHz and
the
resonating capacitor is set at 65 pF.
Calculate
the percentage error introduced
in the
calculated value of Q by the 0.02 W
insertion resistance.
b-) Obtain the equation of RS, LS, CS
and QS for series connection in Q-meter.
4. a-)
Explain the operational principle of a cathode ray oscilloscope (CRO).
b-) In Fig.2.a., find the frequency of the waveform if the time base is set to 0.5 ms/div.
c-) In Fig.2.a., find the rms amplitude of the waveform if the vertical attenuator is set to 2 V/div.
d-) In Fig.2.b., find the period of the waveform if the time base is 10 ms/div.
e-) In Fig.2.b., find the amplitude if the vertical attenuator is set to 1 V/div.
f-) In Fig.2.b., find the slope of the leading edge of the waveform.
Figure
2