Alternating Current

Q. Alternating current can not be measured by dc ammeter because

1. ac cannot pass through dc ammeter
2. Average value of complete cycle is zero
3. ac is virtual
4. ac changes its direction

Q. AC is used for long distance power transmission instead of DC because it is more convenient to step up/down voltage for AC than DC.

1. True
2. False

Q. The power is transmitted from a power house on high voltage ac because

1. Electric current travels faster at higher volts
2. It is more economical due to less power wastage
3. It is difficult to generate power at low voltage
4. Chances of stealing transmission lines are minimized

Q. Figure shows charge $\left(q\right)$ versus voltage $\left(V\right)$ graph for series and parallel combination of two given capacitors. The capacitances are:

1. $40\mu \text{F}$ and $10\mu \text{F}$
2. $60\mu \text{F}$ and $40\mu \text{F}$
3. $50\mu \text{F}$ and $30\mu \text{F}$
4. $20\mu \text{F}$ and $30\mu \text{F}$

Q.

Alternating current can not be measured by dc ammeter because

[AIEEE 2004]

1. ac cannot pass through dc ammeter

2. Average value of complete cycle is zero

3. ac is virtual

4. ac changes its direction

Q. The higher the voltage, the lower the current, lower the current lower the resistance losses in the conductors.

1. False
2. True

Q. Paragraph for below question
नीचे दिए गए प्रश्न के लिए अनुच्छेद

For the shown AC circuit, answer the following questios

दर्शाए गए AC परिपथ के लिए, निम्नलिखित प्रश्न का उत्तर दीजिए।


Q. Phase difference between current I and source voltage is

प्रश्न - धारा I तथा स्रोत वोल्टता के मध्य कलान्तर है

1. 60°
2. 53°
3. 30°
4. 37°

Q. Paragraph for below question
नीचे दिए गए प्रश्न के लिए अनुच्छेद

For the shown AC circuit, answer the following question.

दर्शाए गए AC परिपथ के लिए, निम्नलिखित प्रश्न का उत्तर दीजिए।


Q. Phase difference between current I and source voltage is

प्रश्न - धारा I तथा स्त्रोत वोल्टता के मध्य कलान्तर है

1. 30°
2. Zero
   
   शून्य
3. 60°
4. 45°

Q. Paragraph for below question
नीचे दिए गए प्रश्न के लिए अनुच्छेद

For the shown AC circuit, answer the following question.

दर्शाए गए AC परिपथ के लिए, निम्नलिखित प्रश्न का उत्तर दीजिए।


Q. Phase difference between current I and source voltage is

प्रश्न - धारा I तथा स्रोत वोल्टता के मध्य कलान्तर है

1. 45°
2. 60°
3. 30°
4. 53°

Q. In the given circuit, potential of junction $A$ is :

1. $1.73\text{V}$
2. $4\text{V}$
3. $3.82\text{V}$
4. $2.5\text{V}$

Q. The higher the voltage, the lower the current, lower the current lower the resistance losses in the conductors.

1. False
2. True

Q. Figure shows charge $\left(q\right)$ versus voltage $\left(V\right)$ graph for series and parallel combination of two given capacitors. The capacitances are:

1. $60\mu \text{F}$ and $40\mu \text{F}$
2. $20\mu \text{F}$ and $30\mu \text{F}$
3. $40\mu \text{F}$ and $10\mu \text{F}$
4. $50\mu \text{F}$ and $30\mu \text{F}$

Q. Paragraph for below question

नीचे दिए गए प्रश्न के लिए अनुच्छेद

For the shown AC circuit, answer the following questions.

दर्शाए गए AC परिपथ के लिए, निम्नलिखित प्रश्न का उत्तर दीजिए।


Q. Phase difference between current I and source voltage is

प्रश्न - धारा I तथा स्रोत वोल्टता के मध्य कलान्तर है

1. 22.5°
2. 90°
3. 45°
4. 135°

Q. A $2\mu \text{F}$ capacitor is charged to a potential difference of $10\text{V}$. Another $4\mu \text{F}$ capacitor is charged to a potential difference of $20\text{V}$. The two capacitors are then connected in a single loop, with the positive plate of one connected with negative plate of another. What is the amount of heat dissipated in the circuit ?

1. $600\mu \text{J}$
2. $300\mu \text{J}$
3. $450\mu \text{J}$
4. $900\mu \text{J}$

Q.

The phase difference between input and output voltages of a CE circuit is

1. 0^o

2. 90^o

3. 180^o

4. 270^o

Q. In a region of uniform magnetic induction $B={10}^{-2}tesla$, a circular loop of radius 30 cm and resistance ${\pi }^2$ ohm is rotated about an axis which is perpendicular to the direction of B and which forms a diameter of the loop. If the loop rotates at 200 rpm , the maximum amplitude of the alternating current induced in the loop is

1. $4{\pi }^{2}mA$
2. 30 mA
3. 6 mA
4. 200 mA

Q.

If the flux of magnetic induction through a coil of resistance R and having n turns changes from ${\Phi }_1$ to ${\Phi }_2$, then the magnitude of the charge that passes through the coil is

1. $\frac{{\Phi }_2-{\Phi }_1}{R}$

2. $n\frac{{\Phi }_2-{\Phi }_1}{R}$

3. $\frac{{\Phi }_2-{\Phi }_1}{nR}$

4. $\frac{nR}{{\Phi }_2-{\Phi }_1}$