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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.

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.

r = resistance of the galvanometer l = current through galvanometer = 20mA or 0.02A V1 = p.d across the galvanometer = I X r = 0.02 X r : V1 = 0.02r V2 = p.d across the multiplier = 8 - 0.02r R = resistance of the multiplier = 395\Omega where R = \(\frac{V}{I}\) --> 395 = \(\frac{8−0.02r}{0.02}\) CROSS MULTIPLY 8−0.02r = 395 * 0.02 8−0.02r = 7.9 --> 0.02r = 8 - 7.9 ∴ r = \(\frac{0.1}{0.02}\) = 5\Omega

P = 60w, V = 240v, R = ? P = \(\frac{V^2}{R}\) : 60 = \(\frac{240^2}{R}\) → R * 60 = 57,600 R = \(\frac{57,600}{60}\) R = 960\(\Omega\)

This is because, at resonance, the reactive components (inductive and capacitive reactance) cancel each other out, resulting in only the resistive component contributing to the impedance.

de broglie wavelength formula in terms of kinetic energy: \lambda = \(\frac{h}{\sqrt{2mE}}\) \lambda = \(\frac{6.6 \times 10^{-34}}{\sqrt{2 \times 9.1 \times10^{-31} \times100\times 1.6 \times 10^{-19}}}\) \lambda = 1.22 x 10\(^{-10}\)m NOTE; E = 100eV = 100 x 1.6 x 10\(^{-19}\)J

If the dominant impurity atoms are ACCEPTOR type in the semiconductor, it will have a majority of holes over the electrons [p-type].

Moderation is the process of the reduction of the initial high speed (high kinetic energy) of the free neutron. Since energy is conserved, this reduction of the neutron speed takes place by transfer of energy to a material called a moderator. There are several different types of moderating materials, and each have places where they are used more effectively. Typically-used moderator materials include heavy water, light water, and graphite.

Alpha particles are highly ionising because of their double positive charge, large mass (compared to a beta particle) and because they are relatively slow. They can cause multiple ionisations within a very small distance. And the gamma radiation has the least ionising power.

Gamma rays are produced in the disintegration of radioactive atomic nuclei and in the decay of certain subatomic particles. Gamma radiation is emitted by excited nuclei or other processes involving subatomic particles; it often accompanies alpha or beta radiation, as a nucleus emitting those particles may be left in an excited (higher-energy) state.

De Broglie equation, \lambda = h/mv, is used to describe the wave properties of matter, which suggests that matter can behave as a wave or particles, thereby leading to the wave-particle paradox.

Images formed by plane mirrors are virtual, upright, left-right reversed, the same distance from the mirror as the object's distance, and the same size as the object.