NEW
Font size
WorksheetsAlternating currents
Total questions: 7
Worksheet time: 6mins
An alternating current is one that ...
changes direction periodically.
flows in a fixed direction.
changes only magnitude periodically.
has a fixed magnitude.
An alternating voltage is described by V=240sin400t , where V is in volts. What is the r.m.s. voltage?
240 V
250 V
170 V
340 V
Which best defines the meaning of the r.m.s. value of a sinusoidal alternating current?
Steady current that delivers more power to a resistive load than the mean power of the a.c.
Steady current that delivers the same power to a resistive load as mean power of the a.c.
Alternating current that delivers more power to a resistive load as the mean power of the d.c.
Alternating current that delivers the same mean power to a resistive load as the d.c.
A lamp is connected to a sinusoidal supply. The maximum power transferred by the lamp is 50 W. What is the average power of the lamp.
10 W
25 W
50 W
100 W
A half-wave rectification circuit needs only ____ diode.
1
2
3
4
A bridge rectifier requires at least ____ diode(s).
1
2
4
8
The size of ripple in a rectified current can be reduced by ______.
decreasing resistance of load
increasing capacitance of capacitor
increase supply voltage
connecting additional capacitor in series with existing capacitor
