A bird sitting on a high power line:
1.gets killed instantly
2.gets a mild shock
3.gets a fatal shock
4.is not affected practically
A bird sitting on a high power line:
1.gets killed instantly
2.gets a mild shock
3.gets a fatal shock
4.is not affected practically
A capacitor is connected to a cell of emf E having some internal resistance r, the potential across the:
1.cell is < E
2.cell is E
3.cell is > E
4.capacitor is E
A dielectric is placed in between the two parallel plates of a capacitor as shown in the figure. The dielectric constant of the dielectric being K. If the initial capacity is C, then the new capacity will be:
1.(K + l).C
2.K.C
3.(K+1)2 C
4.(k – l) C
A polythene piece rubbed with wool is found to have a negative charge of 6.4 × 10-9c. How many electrons have been transferred during the process?
1.4 × 1012
2.4 × 1011
3.4 × 1010
4.None of the these
A uniform electric field of 10 NC-1 exists in the vertically downward direction. What is the increase in the electric potential asonegoes up through a height of 300 cm ?
1.15 V
2.30 V
3.45V
4.None of the above
An electric charge of 425 f µC is removed from a fully charged capacitor of capacitance 8.5µF. Its potential will be lowered by:
1.75 V
2.100 V
3.85 V
4.50 V
An electron initially at rest is accelerated through a potential difference of one volt. The energy gained by electron is:
1.1 J
2.1.6 × 10-19 J
3.10-19 J
4.None of the above
Choose the SI unit of electric potential energy :
1.Joule
2.Coulomb
3.Netwon per coulomb
4.Erg
Choose the vector physical quantity:
1.Electric flux
2.Electric potential
3.Electric potential energy
4.Electric intensity
IA capacitor is connected across a battery and the plate separation of capacitor is increased without removing the battery, then:
1.capacitance will increase
2.charge stored will increase
3.energy stored will decrease
4.potential difference will increase
If a +ve charge is moved from low to high potential region, the electric potential energy:
1.decreases
2.increases
3.remain the same
4.may increase or decrease
In the above question:
1.no electrons are transferred
2.electrons are transferred from wool to x polythene
3.electrons are transferred from polythene to wool
4.nothing can be decided
In which of the following forms is the energy stored in a capacitor?
1.Charge
2.Potential
3.Capacitance
4.Electric field
Minimum number of capacitor of 2µF each required to obtain a capacitance of 5µF will be:
1.4
2.3
3.5
4.6
nothing can be decided
1.3.64 × 1020 kg
2.4 × 10-28 kg
3. 4 × 1010 kg
4.None of the these
The amount of work required to increase the distance between -6µC and 4µC from 6 cm to 18 cm will be :
1.1.8 J (
2.2.4 J
3.1.8 µJ
4. 2.4 µJ
The capacitance of a capacitor will decrease if we introduce a slab of:
1.copper
2.aluminium
3.zinc
4.None of these
The capacitance of earth, viewed as a spherical conductor of radius 6408 km is:
1.1420 µF
2.712 µF
3.680 µF
4.540 µF
The dimensions of fall of potential per unit distance are given by:
1.[MLT-3 A-1]
2. [ML2T-2A-1]
3.[ML2T-2A-3]
4.[MLT-2A-2]
The electric potential of earth is taken as:
1.zero
2.infinity
3.unity
4.None of the above
The P.E. of an electric dipole is maximum when it makes an angle θ with electric field. The value of θ is :
1.Ï€2
2.Ï€
3.zero
4.3Ï€2
The surface density of charge is measure:
1.Cm-1
2.Cm-2
3.Cm-3
4.JC-1
Twenty seven drops of mercury are charged simultaneously to the same potential of 10 volts. What will be potential if all the charged drops are made to combine to form one large drop ?
1.180 V
2.90 V
3.120 V
4.45 V
Two capacitors of 3 µF and 6 µF are connected in series with a battery of P.d. 12 V. The P.d. across 3µF and 6µF capacitors respectively will be :
1.8 V, 4 V
2.6 V, 6 V
3. 4 V, 8 V
4.9 V, 3 V
Two capacitors of capacitance 6 µF and 4 µF are put in series across a 120 V battery. What is the potential difference across the 4 µF capacitor ?
1.72 V
2.60 V
3.48 V
4.zero
Two conducting spheres of radii r1 and r2 are equally charged. The ratio of their potential is
1. (r1/r2)²
2.(r1r2)²
3.(r1/r2)
4. (r2/r1)
Two copper spheres of the same radius, one solid and the other hollow, are charged to the same potential. Which will have more charge?
1.Solid sphere
2.Hollow sphere
3.Both will have an equal charge
4.None of the above
What is the number of electrons in 100 g water?
1..35 × 1024
2.3.35 × 1025
3.6.02 × 1023
4.None of the above
When a dielectric slab is introduced between the plates of a parallel plate capacitor which remains connected to a battery then charge on the plates relative to earlier charge is
1.more
2.less
3.less or may be more
4.same
Which of the following is blocked by a capacitor ?
1.A.C.
2.D.C.
3.Both A.C. and D.C.
4.Neither A.C. nor D. C