HELP13

Question

Answer 1

8.1)

Amplitude:

 The Oscilloscope displays a sine wave having vertical divisions and horizontal divisions.

The vertical amplifier scale is 2 V/div.

The horizontal scale is .

The Amplitude of a sine wave is magnitude of maximum voltage to reference line.

Therefore, here vertical divisions from reference line to maximum value.

Amplitude is 6 V.

Solution:

Amplitude is 6 V.

Answer 2

8.2)

The peak-to-peak value: .

is the peak amplitude of the waveform.

Substitute in the above expression.

The peak-to-peak voltage value is 12 V.

Solution:

The peak-to-peak voltage value is 12 V.

Answer 3

8.3)

Period:Time taken by the wave to complete one full cycle.

The time period of a sine wave is number of divisions horizontal scale.

Time period of the wave is .

Frequency: .

Frequency of the wave is 8.33 KHz.

Solution:

Frequency of the wave is 8.33 KHz.

Answer 4

8.4)

Average DC voltage value is 0.637 times of its peak value. 

.

Substitute in the above expression.

Average DC voltage value is 3.822 V.

Solution:

Average DC voltage value is 3.822 V.

Answer 5

7.1)

Three factors of capacitor influence capacitance of a capacitive transducers :

(1) PLATE AREA :

Greater plate area gives greater capacitance and less plate area gives less capacitance.

Larger plate area results in more field flux for a given field force.

(2) PLATE SPACING :

Large plate spacing gives less capacitance and closer plate spacing gives greater capacitance.

Closer spacing results in a greater field force, which results in a greater field flux for any given voltage applied across the plates.

(3) DIELECTRIC MATERIAL :

Greater permittivity of the dielectric gives greater capacitance and less permittivity of the dielectric gives less capacitance.

Materials with a greater permittivity allow for more field flux, so greater collected charge, for any given amount of field force.

Answer 6

7.2)

The speed of a rotation shaft is measured by using Tachometer.

Tachometer :

Tachometer generators are electromechanical devices which output a voltage proportional to their shaft speed. They are used to measure the speed of motors, engines, and other rotational devices.

Tachometer Diagram :

Operation of Tachometer :

These devices use a rotating armature, one end of which is attached to a machine shaft, to measure rotational speed.

The armature rotates within a fixed magnetic field, so that its rotation induces electromotive force proportional to the shaft speed.

The armature contacts are connected to a voltmeter circuit, which converts the voltage into a speed value.

In this particular device, the commutator between the armature and voltmeter circuit serves to convert internally generated AC voltage into DC for compatibility with the voltmeter.

Small permanent magnet motors can be used as tachometer generators in some applications.