An electric spark is struck between two electrodes placed near each other in a closed tank full of petrol. Will the petrol catch fire ? Explain your answer.

How is mutual inductance of a pair of coils affected when (i) separation between the coils in increased, (ii) the number of turns of each coil is increased , (iii) a thin iron sheet is placed between the two coils, other factors ramaining the same ? Explain your answer in each case.

Suppose all the electrons of 100 g water are lumped together to form a negatively charged particle and all the nuclei are lumped together to form a positively charge particle. If these two particles are placed 10.0 cm away from each other, fien the force of attraction between them. Compare it with your weight.

Two friends on roller-skates are standing 5m apart facing eachother. One of them throws a ball of 2kg towards the other, who catches it. How will this activity affect the position of the two? Explain your answer.

Two bar magnets of equal size and strength are placed side by side so tilt the north pole of one magnet is next to the south pole of the other magnet If these magnets are then pushed toward a coil of wire, would you expect an emf to be induced in the coil. Explain your answer

shows two metallic plates A and B placed . parallel to each other at a separaton d. A uniform . electric field E exists between the plates in the direction . from plate B to plate A. Find the potential difference . between the plates.

Two large conducting plates are placed parallel to each other with a separation of d between them. An electron starting from rest near one of the plates reaches the other plate in time t. If e is the charge on the electron and m is its mass, then the surface charge density on the inner surface is

A parallel plate capacitor each with plate area A and separation ‘d’ is charged to a potential difference V. The battery used to charge it is then disconnected. A dielectric slab of thickness d and dielectric constant K is now placed between the plates. What change if any, will take place in (i) charge on the plates (ii) electric field intensity between the plates, (iii) capacitance of the capacitor Justify your answer in each case