Q.4A firm of manufactures, whose books are closed on 31st December purchased machinery for Rs.50, 000 on 15 January, 2016. Additional Machinery was acquired for Rs.10, 000 on 1st July, 2017 and for Rs.16, 466 on 14th April, 2019. Certain machinery, which originally cost Rs.10, 000 in 2016, was sold for Rs.5, 000 on 30th June, 2020. Give the Machinery Account for five years writing off depreciation at 10% by:

(i)Diminishing balance method

(ii)Straight line method​

Consider a uniformly charged ring in the xy plane, centered at the origin. the ring has radius a and positive charge qdistributed evenly along its circumference. a)what is the direction of the electric field at any point on the z axis? . b)what is the magnitude of the electric field along the positive z axis? use k in your answer, where k=14πϵ0. d)the ball will oscillate along the z axis between z=d and z=−d in simple harmonic motion. what will be the angular frequency ω of these oscillations? use the approximation d≪a to simplify your calculation; that is, assume that d2+a2≈a2. express your answer in terms of given charges, dimensions, and constants