Assuming a characteristic impedance of 75 Ω and a load impedance
of 100Ω, find the input
impedance at λ/2, λ and 2λ. How each input impedance will vary for
the case of: i) matched
line; ii) short-circuit line; iii) open circuit line?
6 The single-phase half-wave ac voltage controller in Figure
11.1a has a resistive load of R = 2.5 Ω and the input voltage is Vs
= 208 V (rms), 60 Hz. If the desired output power is Po = 2 kW,
calculate (a) the delay angle α and (b) the input PF.
A 50 ohm transmission line has an unknown load impedance ZL. A
voltage maximum occurs at z = -0.15(wavelength). At z =
-0.20(wavelength) the real part of the impedance is 30 ohms. Find
ZL using the Smith chart.
1) A load can be represented as a 1kOhm resistor. This impedance
is subsequently connected to a sinusoidal 120V (rms) 60Hz voltage
source. Find the current through the load both in phasor form and
in time-domain form. Produce a well-labeled plot showing the
voltage, the current and the power.
a) A load can be represented as a 10μF capacitor connected in
series with a 1kOhm resistor. This impedance is subsequently
connected to a sinusoidal 120V (rms) 60Hz voltage source. Find...
Assuming that the length of a lossless transmission line with
the normalized load impedance of zL = ZL/Z0 = 1 + j1 is l = 2.25λz
, there are a total of (A) 2 voltage maxima and 2 voltage minima
(B) 2 voltage maxima and 3 voltage minima (C) 3 voltage maxima and
2 voltage minima (D) 4 voltage maxima and 4 voltage minima (E) 4
voltage maxima and 5 voltage minima (F) 5 voltage maxima and 4
voltage minima...
A mutual fund has the following fees and expenses. Front
load of 6%, back load of 1%, 12b-1 of 0.25% and annual expenses of
1.5%. The return on the portfolio assets is 12%. Another mutual
fund has the following fees and expenses. Front load of 0%, back
load of 0%, 12b-1 of 2% and annual expenses of 1.5%. The return on
the portfolio assets is 12%.
a)If you invest $10,000 today in both funds, how much
will you have at...
A balanced Y-connected load having an impedance of 60 - j45Ω/ϕ
is connected in parallel with a balanced Δ-connected load having an
impedance of 90√2∠45∘ Ω/ϕ. The paralleled loads are fed from a line
having an impedance of 2 + j2Ω/ϕ. The magnitude of the line-to-line
voltage of the Δ-load is 200√3 V.
Part A: Calculate the magnitude of the phase current in the
Y-connected load.
Part B: Calculate the magnitude of the phase current in the
Δ-connected load.
Part...
In a three-phase circuit the balanced delta load of (36 +j54)
ohms is fed by impedance conductors (5 +j70) ohms. If the generator
voltage is 120 V angle 0° phase A, calculate a) the bc voltage on
the load, b) the powers in the conductors, c) the bc voltage of the
delta load and d) the power delta on the load.
Question 6)
a) What is the RMS value of an AC signal? In case of sinusoidal
signals which relationship exists
between RMS and maximum values? [5 marks]
b) Why AC quantities cannot be added arithmetically as in DC? [5
marks]
Question 7)
Given the following A.C. voltage, v(t) = 80 sin (942t – π/6),
state:
(a) angular frequency [3 marks]
(b) Period [3 marks]
(c) phase difference [4 marks]
Question 2)
Using diagrams, state at least three (3) characteristics of...
Three balanced 3-phase loads are connected in parallel. Load 1
is Y-connected with an impedance of 400 + j300 ? per phase, load 2
is ?-connected with an impedance of 2400 – j1800 ? per phase, and
load 3 is absorbing 172.8 + j2203.2 kVA. The loads are fed from a
set of distribution lines with an impedance of 2 + j16 ? per line.
The magnitude of the line-to-neutral voltage at the load end of the
line is 24?3...