Free Printable Concepts of single phase AC circuit part 1

1.

In purely capacitor circuit

a)

Voltage lead current by 180 degree

b)

Voltage lag current by 180 degree

c)

Current lag voltage by 90 degree

d)

Current lead voltage by 90 degree

2.

In pure resistance single phase circuit

a)

Voltage and current are same

b)

voltage and current are in same phase

3.

Average power in single phase AC circuit is zero. This means circuit is

a)

series RLC circuit

b)

parallel RLC circuit

c)

pure inductive circuit

d)

pure resistance circuit

4.

if $v=V_{0_{\ }}Sin\ \left(314t+13^0\right)$ , the voltage in polar form will be

a)

$\frac{V}{\sqrt{2}}\angle13^0$

b)

$\frac{V_0}{\sqrt{2}}\angle13^0$

c)

$V_0\angle13^0$

d)

$v\angle13^0$

5.

the average value of $\sin^2t\ and\ \sin2t\$ will be

a)

0.5 and 0 respectively

b)

0 and 0.5 respectively

c)

0 and 0

d)

0.5 and 0.5

6.

For a single phase 25 Hz ac system, supply voltage is $100\angle25^0$ . the equivalent sinusoidal volatge is

a)

$v=141.4\sin\left(314t+25^0\right)$

b)

$v=100\sin\left(157t+25^0\right)$

c)

$v=141.4\sin\left(157t+25^0\right)$

d)

$v=100\sin\left(314t+25^0\right)$

7.

For a series R-L circuit having inductive reactance 3 ohm and resistance $\sqrt{3}$ . The power factor will be

a)

0.5

b)

1

c)

0

d)

$\sqrt{3}$

8.

Form factor is given by

a)

Vav/Vrms

b)

Vrms/Vav

c)

Vmax/Vrms

d)

Vrms/Vmax

9.

The power factor is defined as

a)

cosine of the phase difference between voltage and current

b)

ratio of resistance with impedance

c)

ratio of active power with apparent power

d)

All of above

10.

power factor is 0.95 lagging indicates

a)

Current lags to voltage by $\cos^{-1}\left(0.95\right)$

b)

Voltage lags to current by $\cos^{-1}\left(0.95\right)$

c)

any one may correct

d)

both are correct

Concepts of single phase AC circuit part 1

Total questions: 10

Worksheet time: 5mins

Similar Resources on Wayground