Explanation:
According to Kirchhoff’s first law, the current flowing towards the junction is equal to the current leaving the junction. Mathematically, this law can be expressed as ∑nK – 1 IK = 0 (where n is the number of branches carrying current towards or away from the junction)
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
The intensity of the electric field required to keep a water drop of radius 
just suspended in air when charged with one electron is approximately (g = 10 newton/kg e = 1.6 
|
(a) 260 volt/cm |
(b) 260 newton/coulomb |
|
(c) 130 volt/cm |
(d) 130 newton/coulomb |
A current of 10A is passing through a long wire which has semicircular loop of the radius 20cm as shown in the figure. Magnetic field produced at the centre of the loop is
|
(a) 10 πμT |
(b) 5 πμT |
(c) 4 πμT |
(d) 2 πμT |
If a coil of metal wire is kept stationary in a non-uniform magnetic field, then
|
(a) An e.m.f. is induced in the coil |
(b) A current is induced in the coil |
|
(c) Neither e.m.f. nor current is induced |
(d) Both e.m.f. and current is induced |
In the circuit shown, a meter bridge is in its balanced state. The meter bridge wire has a resistance 0.1 ohm/cm. The value of unknown resistance X and the current drawn from the battery of negligible resistance is
|
(a) 6 W, 5 amp |
(b) 10 W, 0.1 amp |
(c) 4 W, 1.0 amp |
(d) 12 W, 0.5 amp |
Three long, straight and parallel wires carrying currents are arranged as shown in the figure. The wire C which carries a current of 5.0 amp is so placed that it experiences no force. The distance of wire C from wire D is then
|
(a) 9 cm |
(b) 7 cm |
(c) 5 cm |
(d) 3 cm |
Assertion : NAND or NOR gates are called digital building blocks.
Reason : The repeated use of NAND (or NOR) gates can produce all the basic or complicated gates.
|
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |
An a particle is accelerated through a p.d of 
volt then K.E. of particle will be
|
(a) 8 MeV |
(b) 4 MeV |
(c) 2 MeV |
(d) 1 MeV |
In the circuit as shown in the figure the effective capacitance between A and B is
|
(a) 3 μF |
(b) 2 μF |
(c) 4 μF |
(d) 8 μF |