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The electric field at the surface of the conductor is perpendicular to the surface. Charge accumulates, and the field is strongest, on pointy parts of the conductor.

The magnetic meridian is an equivalent imaginary line connecting the magnetic south and north poles and can be taken as the horizontal component of magnetic force lines along the surface of the earth. Therefore, a compass needle will be parallel to the magnetic meridian.

Ferrite magnets are non-conductive aferromagnetic ceramic compounds derived from iron oxides such as Haematite (Fe203) or Magnetite (Fe304) and other metal oxides such as Barium and Strontium. Ferrite is a polycrystal, sintered material with high electrical resistivity. The high resistance of ferrite makes eddy current losses extremely low at high frequencies.

When it is cut into two, the two cut pieces will have their own north and south poles.

If both the coil and the magnet are stationary, then there is no change in the magnetic flux and hence no current is induced in the coil.

Relays are electrically operated switches that open and close the circuits by receiving electrical signals from outside sources.

the magnetic flux through a surface is the surface integral of the normal component of the magnetic field B over that surface. It is usually denoted Φ or ΦB. The SI unit of magnetic flux is the weber Mathematically it is represented as B = Φ/A where B is magnetic flux density in teslas (T), Φ is magnetic flux in webers (Wb), and A is area in square meters (m2).

Sensitivity of a galvanometer increases when number of turns, area of coil and magnetic field increase

Two conductors with current flowing in the same direction will attract.

The greatest force is experienced when the conductor is at right angle to the field. I.e at perpendicular or Ø = 90^\circ

The potential energy for a positive charge increases when it moves against an electric field(from lower potential to higher potential), And decreases when it moves with the electric field((from higher potential to lower potential); The opposite is true for a negative charge. Unless the unit charge crosses a changing magnetic field, its potential at any given point does not depend on the path taken.

Therefore, as the area of the plates increase, capacitance increases.

Given Data: Emf = 1v, r = 2 ohms, R = 3 ohms, I = ? 3 resistance in parallel = \(\frac{1}{r_1}\) + \(\frac{1}{r_2}\) + \(\frac{1}{r_3}\) \(\frac{1}{r_T}\)= \(\frac{1}{2}\) + \(\frac{1}{2}\) + \(\frac{1}{2}\) \(\frac{1}{r_T}\) = \(\frac{1+1+1}{2}\) \(\frac{1}{r_T}\) = \(\frac{3}{2}\) cross multiply r\(_T\) = \(\frac{2}{3}\) or 0.67 E = I(R+r) 1 = I(3+0.67) 1 = I(3.67) 1 \div 3.67 = I 0.27 = I : I ≈ 0.30A

Earthing of an electrical appliance meant the outer metallic case of appliance is connected with earth, wire which is welded to the end of a copper rod and it is burned in the ground. It save the appliance during short-circuiting by passing Excessive current to earth.

If the zinc used in the simple cell is of the impure commercial variety bubbles of hydrogen will be seen coming off the zinc. This is called local action.