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 \(+q\) is placed at the origin \(O.\) Work done in taking another point charge \(-Q\) from the point \(A,\) coordinates \((0,a),\) to another point \(B,\) coordinates \((a,0),\) along the straight path \(AB\) is:
1. | \( \left(\dfrac{-{qQ}}{4 \pi \varepsilon_0} \dfrac{1}{{a}^2}\right) \sqrt{2} {a}\) | 2. | zero |
3. | \( \left(\dfrac{qQ}{4 \pi \varepsilon_0} \dfrac{1}{{a}^2}\right) \dfrac{1}{\sqrt{2}} \) | 4. | \( \left(\dfrac{{qQ}}{4 \pi \varepsilon_0} \dfrac{1}{{a}^2}\right) \sqrt{2} {a}\) |
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 \({A}\) and \(B\) 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 \(2~\text {gm}\) has a charge of \(2~\mu\text{C}.\) Through what potential difference must it be accelerated, starting from rest, to acquire a speed of \(10~\text{m/s}?\)
1. \(50~\text {kV}\)
2. \(5~\text {V}\)
3. \(50~\text {V}\)
4. \(5~\text {kV}\)
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. |
A capacitor of capacity \(C_1\) is charged up to \(V\) volt and then connected to an uncharged capacitor \(C_2\). Then final P.D. across each will be:
1. \(\frac{C_{2} V}{C_{1} + C_{2}}\)
2. \(\frac{C_{1} V}{C_{1} + C_{2}}\)
3. \(\left(1 + \frac{C_{2}}{C_{1}}\right)\)
4. \(\left(1 - \frac{C_{2}}{C_{1}} \right) V\)