A capacitor is charged with a battery and energy stored is U. After disconnecting the battery another capacitor of the same capacity is connected in parallel with it. The energy stored in each capacitor is:
1. U/2
2. U/4
3. 4 U
4. 2 U
Two charges q1 and q2 are placed 30 cm apart, as shown in the figure. A third charge q3 is moved along the arc of a circle of radius 40 cm from C to D. The change in the potential energy of the system is , where k is:
.
1. 8q2
2. 6q2
3. 8q1
4. 6q1
As per this diagram, a point charge \(\mathrm{+q}\) is placed at the origin \(\mathrm{O}.\) Work done in taking another point charge \(\mathrm{-Q}\) from the point \(\mathrm{A},\) coordinates \((\mathrm{0,a}),\) to another point \(\mathrm{B},\) coordinates \((\mathrm{a,0}),\) along the straight path \(\mathrm{AB}\) is:
1. | \( \left(\frac{-\mathrm{qQ}}{4 \pi \varepsilon_0} \frac{1}{\mathrm{a}^2}\right) \sqrt{2} \mathrm{a}\) | 2. | zero |
3. | \( \left(\frac{\mathrm{qQ}}{4 \pi \varepsilon_0} \frac{1}{\mathrm{a}^2}\right) \frac{1}{\sqrt{2}} \) | 4. | \( \left(\frac{\mathrm{qQ}}{4 \pi \varepsilon_0} \frac{1}{\mathrm{a}^2}\right) \sqrt{2} \mathrm{a}\) |
A network of four capacitors of capacity equal to is conducted to a battery as shown in the figure. The ratio of the charges on is:
1.
2.
3.
4.
The effective capacity of the network between terminals \(\mathrm{A}\) and \(\mathrm{B}\) is:
1. | \(6~\mu\text{F}~\) | 2. | \(20~\mu\text{F} ~\) |
3. | \(3~\mu\text{F}~\) | 4. | \(10~\mu\text{F}\) |
1. | \(40\) V | 2. | \(10\) V |
3. | \(30\) V | 4. | \(20\) V |
A bullet of mass \(2\) g is having a charge of \(2\) µC. Through what potential difference must it be accelerated, starting from rest, to acquire a speed of \(10\) m/s?
1. \(50\) kV
2. \(5\) V
3. \(50\) V
4. \(5\) kV
1. | \(q\cdot E\) and \(p\cdot E \) |
2. | zero and minimum |
3. | \(q\cdot E\) and maximum |
4. | \(2q\cdot E\) and minimum |
1. | \(6 E,6 C\) | 2. | \( E,C\) |
3. | \(\frac{E}{6},6C\) | 4. | \(E,6C\) |
Some charge is being given to a conductor. Then it's potential:
1. | is maximum at the surface. |
2. | is maximum at the centre. |
3. | remains the same throughout the conductor. |
4. | is maximum somewhere between the surface and the centre. |