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When a radioactive source emits radiations that are deflected by both magnetic and electric fields, the radiations are likely to be beta particles (\beta particles). Beta particles(\beta): These are high-energy, high-speed electrons (\beta-) or positrons (\beta+). They are negatively or positively charged, respectively, and are deflected by both electric and magnetic fields due to their charge and lower mass compared to alpha particles. Gamma rays (γ): These are high-energy electromagnetic radiation and are neutral, meaning they are not deflected by electric or magnetic fields. Alpha particles (\alpha): These are positively charged and consist of two protons and two neutrons. They are not significantly deflected by electric or magnetic fields due to their relatively large mass and low speed.

Inductive reactance is given by XL = WL = 2πfL XL = 2 x π x (50/π) x 2 XL = 200Ω

Efficiency = Output/input x 100/1 Efficiency = 3/(3+1) x 100/1 = 3/4 x 100/1 = 75%

The force on the conductor is maximum when the conductor lies perpendicular to the field during which the maximum force is given as; F = ILB = 0.8 x 2 x 0.5 = 0.8N

For a photoemitted electron, eV = K.E.max, where V = stopping potential and K.E. = maximum kinetic energy of the photo emitted electron given by K.E. = Energy of incident rad - Work function = 5ev - 3ev = 2ev ∴ eV = 2eV V = 2eV/e = 2V ∴ Stopping Potential = 2.0V

An astronomical telescope traditionally consists of two converging lenses with the objective having a longer focal length than the eyepiece. In this case, the 50 cm lens would serve as the objective, and the 5 cm lens as the eyepiece, which is a standard configuration for astronomical telescopes.

In a pure (intrinsic) semiconductor, the number of electrons in the conduction band is equal to the number of holes in the valence band. This is because when an electron moves from the valence band to the conduction band, it leaves behind a hole.

In thermonuclear reactions, Energy = ∆mC\(^2\) ∆m = Change in Mass C = Speed of light ∴ 5.02 x 10\(^{-27}\) - 5.01 x 10\(^{-27}\) x [3 x 10\(^8\)]\(^2\) 0.01 x 10\(^{-27}\) x 9 x 10\(^{16}\) E = 9.0 x 10\(^{-13}\)J

The velocity V = 10 + 2t\(^2\) But acceleration, a = dv/dt thus if V = 10 + 2t\(^2\) dv/dt = 4t And t = 5s then a = 4x5 = 20m/s\(^2\) ∴ a = 20m/s\(^2\)

For a simple pendulum, the period T = 2π \sqrt 1/g Since g, 2 and π are constant, => T ∝ √l ∴ T = K√l Let the original length = l thus for the length l, period T = 17s ∴ 17 = K√1 .................. [1] Again, for the new length [1 - 1.5] the period T = 8.5s ∴ 8.5 = k \sqrt [1-1.5] ...............[2] thus dividing eqn [1] by eqn[2] we have 17/8.5 = √(l/l-1.5) ∴2 = √(l/l-1.5) =>4 = (l/l-1.5) ∴l = 4[l-1.5] = 4l - 6.0 ∴4l - l = 6.0 3l = 6.0 l = 2.0m

For a vibrating sonometer wire, the frequency F = l/2l \sqrt(T/m) and if the length, l and mass per unit length, m, are constant, then Fo ∝ \sqrtT => FoK\sqrtT or Fo/\sqrtT = K => F1o/\sqrtF1 = F2o/\sqrtF2 ∴ F1o/\sqrtT1 = F2o/\sqrtT2 thus F2 = F3x\sqrt(2T1 __\sqrtT1 = = Fox\sqrt2 x \sqrtT1 \sqrtT1 ∴F2 = Fo x \sqrt2 = Fox\sqrt2

The general wave equation is given by Y = sin A 2π/λ [x - vt] = Sin A [(2π X)/λ - (2π vt)/λ] thus if A = 0.15;λ = 0.01m; f = 550Hz then V = f x λ = 550 x 0.01 = 5.50m/s ∴ Y = 0.15 sin [(2 x λ x X)/0.01 - (2 x λ x 5.5t)/0.01] = 0.15 sin[200λX - 200 x λ x 5.5t] ∴ Y = 0.15 sin 200λ[x - 5.5t]

For transverse wave on string velocity V = \(\sqrt{\frac{T}{M}}\) where T is the tension, and M is the mass per unit length ∴ for T = 12N and M = 3.0 x 10\(^{-2}\)kgm\(^{-1}\) V = \(\sqrt{\frac{12}{3.0 \times10^{-2}}}\) V = \(\sqrt{\frac{1200}{3}}\) = \(\sqrt{400}\) ∴ V = 20m/s

Angle of deviation = 180 - [i + v] = 180 - 2i [since i = v] ∴ 120 = 180 - 2i 2i = 180 - 120 = 60 ∴ i = 30o

The Six's maximum and minimum thermometer uses a liquid-filled bulb connected to a U-shaped tube with a mercury thread. As the liquid expands or contracts, the mercury moves, pushing the steel indexes to indicate the maximum and minimum temperatures, which can be reset using a magnet.