An AC source with ΔVmax = 140 V and f = 60.0 Hz is connected between points a and d in the figure.

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An AC source with ΔVmax = 140 V and f = 60.0 Hz is connected between points a and d in the figure.

(a) Calculate the maximum voltages between points a and b.

(b) Calculate the maximum voltages between points b and c.

(c) Calculate the maximum voltages between points c and d.

(d) Calculate the maximum voltages between points b and d.
asked Mar 19, 2012 in Physics by yoshi ~Expert~ (919 points)

1 Answer

+1 vote

The maxium voltage between each set of point can be established using Ohm's Law:

Vmax' =  Imax * R  (*where Vmax' = max voltage between the points and not the same as the Vmax given in question, Imax = max current, R = resistance )

So first we need to find Imax before going any further:

Imax = Vmax / Z        (*where Imax = max current, Vmax = max voltage of source, which is given in question, Z = impedance)

So no we need to find Z:

Z =  R^2 + (XL - XC)^2      (*where R = resistance, XL = inductive reactance, XC = capactive reactance)

Now we need to find XL and XC :

XL = ω*L      (*where ω = angular frequency, L = inductance)

XC = 1 / ω*C     (*where ω = angular frequency, C = capacitance)

and ω is equal to:

ω = 2*pi*f    (*where f = frequency in Hz)

After solving for XL and XC, you can then solve for Z.

Next after solving for Z, you can find Imax


Now that you have Imax, you can proceed to use

Vmax' =  Imax * R

where R is resistance between each est of points.

For example Resistance between points a and b is 40 ohm,

between b and c is XL

between c and d is XC


For Part D, the voltage between points b and d is the voltage in part B minus the voltage in Part C


answered Mar 25, 2012 by kirby ~Expert~ (3,020 points)
edited Mar 25, 2012 by kirby