Class name Subject Book title Chapter number Content Created at
Class XII Accountancy Computerised Accounting System 2 January 1, 1900. Numbers to the right of the decimal point in the serial number represent the time; numbers to the left represent the date. For exa...
Class XI Physics Physics Part-II 7 C HAPTER F OURTEEN W AVES 14.1 INTRODUCTION In the previous Chapter, we studied the motion of objects oscillating in isolation. What happens in a s...
Class XI Physics Physics Part-II 7 that propagate from one point to another. All our communications essentially depend on transmission of signals through waves. Speech means producti...
Class XI Physics Physics Part-II 7 on. The disturbance moves Light, radiowaves, X-rays, are all electromagnetic from one end to the other; but each spring only waves. In vacuum, all ...
Class XI Physics Physics Part-II 7 a region is compressed, the molecules first scientific analysis of wave motion dates back in that region are packed together, and they tend to move...
Class XI Physics Physics Part-II 7 wave propagation. involves oscillations of constituents of the position as the pulse or wave passes through medium. If the constituents of the medi...
Class XI Physics Physics Part-II 7 periodic sinusoidal up Fig. 14.4 Longitudinal waves (sound) generated in a and down jerk to one end of the string. The pipe filled with air by movi...
Class XI Physics Physics Part-II 7 14.3 DISPLACEMENT RELATION IN A PROGRESSIVE WAVE sustain shearing stress, such as solids and not in fluids. Fluids, as well as, solids can sustain ...
Class XI Physics Physics Part-II 7 diminishing amplitude to the very bottom. The y(x,t) = Asin(kx − ω t)+ Bcos(kx − ωt) (14.3) particle motion in water waves involves a From Equation...
Class XI Physics Physics Part-II 7 k : angular wave number positivedirectionofx-axisatdifferenttimes. kx– t+ : initial phase angle (a+x = 0, t = 0) Using the plots of Fig. 14.6, we n...
Class XI Physics Physics Part-II 7 x = 0 origin oscillates about its mean position as the wave progresses. This is true for any other and t = 0. Hence, is called the initial phase lo...
Class XI Physics Physics Part-II 7 –1 therefore, use dimensional analysis. We already know that dimensional analysis alone can never Tension, T = 60 N yield the exact formula. The ov...
Class XI Physics Physics Part-II 7 distance between points with the same –1 displacement (at any given instant of time) is Its SI unit is rad s . The frequency ν is the obtained by t...
Class XI Physics Physics Part-II 7 could be dropped and the units could be written merely as m . Thus, k reprπsents 2 times the number of waves (or the total phase difference) that c...
Class XI Physics Physics Part-II 7 speed v (otherwise the wave pattern will not λ = 2π/k remain fixed). The motion of a fixed phase point on the wave is given by 2π = −1 kx – ωt = co...
Class XI Physics Physics Part-II 7 2026-27 WAVES 285 the speed; Eq. (14.12) then relates wavelength to arising due to an external force). It does not frequency for the given speed. O...
Class XI Physics Physics Part-II 7 inspection reveals and µ (T is a property of the stretched string that quantity B/ ρ has the relevant dimension: Reprint 2026-27 286 PHYSICS −2 −2 ...
Class XI Physics Physics Part-II 7 case is the same that as before and yields a relation like Eq. (14.18), V∆P + P∆V = 0 with an undetermined C, which the exact derivation shows to b...
Class XI Physics Physics Part-II 7 was pointed out by Laplace that the pressure variations in the propagation of sound waves are so fast that there is little time for the heat flow t...
Class XI Physics Physics Part-II 7 waves arrive in a region OFWAVES simultaneously, and therefore, overlap, the net displacement y (x,t) is given by What happens when two wave pulses...
Class XI Physics Physics Part-II 7 in phase, and y 2x, t) = a sin (kx – t + ) (14.28) y t  2a sin k  t (14.33) The net displacement is then, by the principle of superposition,...
Class XI Physics Physics Part-II 7 waves differ by a phase of π, so that yr(x, t) = a sin (kxω–t + 0). the resultant displacement is zero. This = a sin (kx –ω t) (14.36) reasoning is...
Class XI Physics Physics Part-II 7 t) + sin (kx + t)] nodes; the points at which the amplitude is the Using the familiar trigonometric identity largest are called antinodes. Fig. 14....
Class XI Physics Physics Part-II 7 is different at different locations. The points at which the amplitude is n  zero (i.e., where there is no motion at all) are x = ; n = 0, 1, 2, 3...
Class XI Physics Physics Part-II 7 case of a stretched string of length L fixed at both ends. Taking one end to be at x = 0, the boundary conditions are that x = 0 and x = L are posi...