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For a refractive index () = \(\frac{\sin\frac{1}{2} (A + D)}{\sin\frac{1}{2}A}\) D = angle of minimum deviation A = refractive angle of the prism 1.5 = \(\frac{\sin\frac{1}{2} (60 + D)}{\sin\frac{1}{2} \times 60}\) 1.5 = \(\frac{\sin\frac{1}{2} (60 + D)}{\sin 30}\) Sin \(\frac{1}{2}\) (60 + D) = 1.5 * Sin 30 Sin \(\frac{1}{2}\) (60 + D) = 0.75 \(\frac{1}{2}\) (60 + D) = Sin-1 (0.75) but Sin-1 (0.75) = 49o \(\frac{1}{2}\) (60 + D) = 49 60 + D = 2 * 49 = 98o D = 98o - 60o D = 38o

Seven 40W lamps = 7 \times 40 = 280W Five 80W lamps = 5 \times 80 = 400W Total power = 280W + 400W = 680W = \(\frac{680KW}{1000}\) = 0.68KW The kilowatt hour = 0.68 KW \times 12 hrs = 8.16 KWh Cost is N 7 per KWh So the cost of running them = 8.16KWh \times N 7/KWh = 57.12

V = IR from ohms law I = \(\frac{V}{R}\) Since the resistances are in parallel \(\frac{1}{Reff}\) = \(\frac{1}{18}\) + \(\frac{1}{12}\) + \(\frac{1}{6}\) = \(\frac{2 + 3 + 6}{36}\) = \(\frac{11}{36}\) R\(_{eff}\) = \(\frac{36}{11}\) = 3.27 I = I\(_1\) + I\(_2\) + I\(_3\) = \(\frac{V}{Reff}\)= \(\frac{12}{3.27}\) = 3.669A I = 3.7A

u = , H = 20, g = 10 From equation of motion under gravity H = ut ± \(\frac{1}{2}\)gt2, It is falling so g is +ve H = 0 + \(\frac{1}{2}\)gt2 H = \(\frac{1}{2}\)gt2 2H = gt2 \(\frac{2H}{g}\) = t2 t = \(\frac{\sqrt{2H}}{g}\) = \(\frac{\sqrt {2 \times 20}}{10}\) = √4 = 2s

Mechanical waves require material medium for their propagation only radio waves among the options docs require a material medium

Consider an inclined plane shown below, as the effort moves along OB, the load moves is lifted up through a vertical height AB V.R = \(\frac{\text{distance moved by effort}}{\text{distance moved by load}}\) = \(\frac{OB}{AB}\) But Sinθ = \(\frac{opp}{hyp}\) = \(\frac{AB}{OB}\) therefore; = \(\frac{OB}{AB}\) = \(\frac{1}{\sin \theta}\)

Using boyle's law P1V1 = P2V2 V2 = \(\frac{P_1 V_1}{200}\) = \(\frac{400 \times 10}{200}\) = 20cm3

An atom can be represented thus, \(^{Z}_{A}X\) where Z = mass number A = atomic number A = number of proton = number of electrons in a free state = 28 Z = number of protons + number of neutrons = 28 + 30 = 58 \(^{58}_{28}X\)is the representation

No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option A.

No expanded working has been attached for this question yet. The verified answer is Option A.

Alkanones also known as ketones have the general formula RCOR'

Constituents of duralumin are: Al, Cu, Mg, Mn. Constituents of Alnico are: Al, Ni and Co In 1909, the alloy of duralumin was discovered by Alfred Wilon consisting of 94% Al, 4% Cu, 1% Mg and 1% Mn(Manganese) Alnico is an acronym referring to a family of iron alloys which in addition to iron are composed primarily of Al, Ni and Co.

The shape of the S-orbital is spherical.

Aluminium hydroxide is used in the dyeing industry as a mordant. It combines with a dye and thereby fixes it in a material.