Kinetic energy of an electron accelerated in a potential difference of 100 V is
1. 1.6 × 10–17 J
2. 1.6 × 1021 J
3. 1.6 × 10–29 J
4. 1.6 × 10–34 J
When one electron is taken towards the other electron, then the electric potential energy of the system -
1. Decreases
2. Increases
3. Remains unchanged
4. Becomes zero
Equipotential surfaces associated with an electric field which is increasing in magnitude along the x-direction are
1. Planes parallel to yz-plane
2. Planes parallel to xy-plane
3. Planes parallel to xz-plane
4. Coaxial cylinders of increasing radii around the x-axis
Point charge q1 = 2 μC and q2 = –1 μC are kept at points x = 0 and x = 6 respectively. Electrical potential will be zero at points
1. x = 2 and x = 9
2. x = 1 and x = 5
3. x = 4 and x = 12
4. x = –2 and x = 2
A proton is about 1840 times heavier than an electron. When it is accelerated by a potential difference of 1 kV, its kinetic energy will be -
1. 1840 keV
2. 1/1840 keV
3. 1 keV
4. 920 keV
A thin spherical conducting shell of radius \(R\) has a charge \(q.\) Another charge \(Q\) is placed at the centre of the shell. The electrostatic potential at a point \(P\) which is at a distance \(\frac{R}{2}\) from the centre of the shell is:
1. \(\frac{\left( q + Q \right)}{4 \pi \varepsilon_{0}} \frac{2}{R}\)
2. \(\frac{2 Q}{4 \pi \varepsilon_{0} R}\)
3. \(\frac{2 Q}{4 \pi \varepsilon_{0} R} - \frac{2 q}{4 \pi \varepsilon_{0} R}\)
4. \(\frac{2 Q}{4 \pi \varepsilon_{0} R} + \frac{q}{4 \pi \varepsilon_{0} R}\)
If identical charges (–q) are placed at each corner of a cube of side b, then electric potential energy of charge (+q) which is placed at centre of the cube will be -
1.
2.
3.
4.
Four charges are placed at the corners of a square taken in order. At the centre of the square
1.
2.
3.
4.
A charge of \(10\) e.s.u. is placed at a distance of \(2\) cm from a charge of \(40\) e.s.u. and \(4\) cm from another charge of \(20\) e.s.u. The potential energy of the charge \(10\) e.s.u. is: (in ergs)
1. | \(87.5\) | 2. | \(112.5\) |
3. | \(150\) | 4. | \(250\) |
A sphere of 4 cm radius is suspended within a hollow sphere of 6 cm radius. The inner sphere is charged to potential 3 e.s.u. and the outer sphere is earthed. The charge on the inner sphere is
1. 54 e.s.u.
2. e.s.u.
3. 30 e.s.u.
4. 36 e.s.u.