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Length of string of a musical instrument is varied from Lo to 2Lo in 4 different cases. Wire is made of different materials of mass per unit length μ, 2μ, 3μ, 4μ respectively. For first case (string – 1) length is Lo, Tension is To then fundamental frequency is fo, for second case length of the string is 3L0/2 (3rd Harmonic), for third case length of the string is 5L0/4 (5th Harmonic) and for the fourth case length of the string is 7L0/4 (14th harmonic). If frequency of all is same then tension in strings in terms of To will be:

a) String - 1 (P) T0 b) String – 2 (Q) T0/√2 c) String - 3 (R) T0/2 d) String - 4 (S) T0/16 (T) 3T0/16 Answer:... View Article

Perfectly reflecting mirror of mass M mounted on a spring constitute a spring mass system of angular frequency Ω such that [4πMΩ]/h = 1024 m-2 where h is plank constant. N photons of wavelength λ = 8π x 10-6 m strikes the mirror simultaneously at normal incidence such that the mirror gets displaced by 1 μm. If the value of N is x * 1012, then find the value of x.

Photons are reflected MV = 2Nh/λ [mean] Vmean = αA A = 1 min N = N = 4Mπα/h x 10-12 1024 x 10-12 1 x 10-12 Therefore, X = 1... View Article