Short Answer TypeAn isolated 16 μF parallel plate air capacitor has a potential differences of 1000 V (Figure 5 a). A dielectric slab having relative permittivity (i.e. dielectric constant) = 5 is introduced to fill the space between the two plates com pletely. (Figure 5 b). Calculate:
(i) The new capacitance of the capacitor.
(ii) The new potential differences between the two plates of the capacitor
An electron revolves around the nucleus of hydrogen atom in a circular orbit of radius 5 x 10-11 m. Calculate
(i) Intensity of electric field of the nucleus at the position of the electron.
(ii) Electrostatic potential energy of the hydrogen nucleus and electron system.
(i) Peltier effect: If the junctions of a thermocouple are at the same temperature and a current is passed round the circuit of the thermocouple, heat is produced at one junction and absorbed at the other i.e. one junction is heated and other junction is cooled then this defect is called Peltier effect.
The difference between Peltier effect and Seebeck effect is that they are reverse of one another.
(ii) The statement “Temperature Coefficient of resistance of a metal is 4 x 10-3 / °C means that if 1 °C temperature of metal is increased then the charge in resistance will be 4 x 10-3ohm.
In the circuit shown below, PQ is a uniform metallic wire of length 4 m and resistance 20 Ω. Battery B has an emf of 10V and internal resistance of 1 Ω. J is a jockey or slide contact. Resistance of the ammeter and connecting wires is negligible.
(i) When the jockey J does not touch the wire PQ, what is the reading of ammeter A?
(ii) Where should the jockey J be pressed on the wire PQ so that the galvanometer G shows no deflection?
is kept in two uniform and perpendicular magnetic fields 
as shown below:
(i) What is the effect of each of the magnetic fields
on the needle?
(ii) When the needle is in equilibrium, obtain an expression for an angle θ made by the needle with 
in terms 
of only.
at a point M which lies exactly midway between PQ and RS. 
Switch
