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F = uv ; v = 1u 12 = \(\frac{v + 3v}{v + 3v}\) v = 16cm, u = 48cm distance between U and V = 48 - 16 =32cm

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

In solids, sound can exist as either a longitudinal or a transverse wave. But in mediums which are fluid (e.g., gases and liquids), sound waves can only be longitudinal. For Longitudinal Waves, the displacement of the medium is parallel to the direction of propagation of the wave.

(a) The laws of electromagnetic induction states that (1) whenever there is a change in the magnetic flux linked with a circuit, an e.m.f. is induced, the strength of which is proportional to the rate of change of the flux linked with the circuit. The above law is sometimes called faraday's law of electromagnetic induction. (2) The direction of the induced current is always such as to oppose the change producing it. This is called Lenz's law. b(i) Experiment to show how an induced e.m.f. can be produced. A coil with many turns is connected to centre-scale zero galvanometer G. As the bar magnet is moved rapidly close and through the turns, an induced e.m.f. is produced. The galvanometer pointer is deflected showing a flow of current. The same effects could be observed if the coil is moving towards the magnet instead. Or as long as there is relative motion between the two. (ii) The magnitude of the induced e.m.f. depends on: (1) The magnitude of flux linking the coil. (2) The relative speed between the magnet and the coil. (c) The root-mean-square (r.m.s.) value of an alternating current is the steady or direct current which produces the same heating effect per secoridin a given resistor. Its relationship with the peak value of alternating current \(I_{o}\) is given by \(I_{r.m.s} = \frac{1}{\sqrt{2}} I_{o}\) d(i) \(I\) is the instantaneous current \(I_{o}\) is the peak value of the current \(\alpha\) is the angular frequency \(\alpha t\) is the phase or the current (since it is wave-like). (ii) \(I = I_{o} \sin \alpha t\) = \(I_{r.m.s} \sqrt{2} \sin 30^\circ\) = \(\sqrt{2} \times 15 \times \frac{1}{2} = 10.6A\)

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

\(n_1 \sin(\theta_1)\) = \(n_2 \sin(\theta_2\) BUT, n = \(\frac{c}{v}\), where c is the speed of light in vacuum (approximately equal to the speed of light in air) and v is the speed of light in the medium. For air, n\(_1\) = \(\frac{3 \times 10^8}{3 \times 10^8}\) = 1 For glass, n\(_2\) = \(\frac{3 \times 10^8}{1.8 \times 10^8}\) ≈ 1.667 Applying snell's law: \(n_1 \sin(\theta_1)\) = \(n_2 \sin(\theta_2)\) = \(1 \sin(\theta_1)\) = 1.667 sin(30) = 0.83335 Thus, the sine of the angle of incidence is ≈ 0.8

F = 24cm , U = -36cm(behind lense) Applying Lense formula = \(\frac {1}{f} = \frac{1}{v} - \frac{1}{u}\) \(\frac{1}{v} = \frac{1}{24} - \frac{1}{36} = \frac{1}{72}\) v = 72cm but Magnification = \(\frac{V}{U} = \frac{h^i}{h_o}\) \(\frac{72}{-36} = \frac{-4}{h_o}\) \( h_1\) = -4( real image is negative) by cross multiplying \(h_1\) = 2cm

T = λ/v T = 1.65/330 = 0.005

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

X = vt/2 = (340 x 0.5)/2 = 85m

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

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 D.

F = \(\frac{1}{2L}\)\(\sqrt\frac {T}{m}\) N:B m is mass per length = \(\frac {0.01}{0.5}\) = 0.02kgm-1 F = \(\frac{1}{2\times 0.5}\)\(\sqrt\frac {800}{0.02}\) = 200Hz

Distance = 340 x 2 = 680m