Homework 5
Magnetic Force
For the actuator shown above: N = 500
A = (20 mm)2 = 4.010-4 m2
i = 3.0 A
Calculate the flux density B(x) [T], the flux (x) [Wb], the coil inductance L(x) [H], and the
electromagnetic force fe(x) [N] on the plunger (shown in gree
Homework 4 Wheatstone bridge - Spring 2011
VT
10 k
Rx
10 V
VL
Vo
VR
10 k
1 k
0
The voltmeter (shown by a circle in the diagram) is almost an open circuit, so
you may neglect its current.
(a) Develop an expression for the voltmeter reading Vo in terms of R
Homework 3 - Spring 2011.
A two-wire dc power distribution circuit supplies six 100 W lamps located 250 ft from a
dc generator. The generator voltage is 120 V and the lamp voltage should be 110 V or
more. Calculate the current drawn by each lamp if its vo
ELCT 220
Spring 2011
Homework 2
(a) Two resistors are connected in series R1 = 12 k and R2 = 9.1 k. Sketch a circuit showing the series
connection of these two resistors with a battery. Calculate the series equivalent of the two resistors. If
the battery
ELCT 220
Spring 2011
Homework 1
1. Two resistors R1 = 5.6 k and R2 = 3.3 k are to be connected in series. Calculate the series
equivalent resistance Rs.
2. The same two resistors are reconnected in parallel. Calculate the parallel equivalent resistance
Rp
Extra credit problems spring 2011
1.5
12 V
1.0
15
1.2
22
1.1
33
12 V
1. Set up mesh current equations. Sketch the circuit showing the mesh current directions.
2. Set up node voltage equations. Sketch the circuit showing the node voltage polarities.