Most Important Selected Qs for JEE AdvancedPhysicsMechanical Properties of Solids
In the adjacent figure, ABCD are four points in a smooth horizontal plane representing the four corners of a square of diagonal 20 cm . A very small object of mass 14 gm placed at the centre of the square connected to points A, B, C and D by four elastic strings of same dimensions but of different moduli of elasticity as shown in the figure. Natural length and cross-sectional area of each string are 10 cm and ^2 10⁻⁶
Correct answer
1
Step-by-step solution
aligned & T = [ m 9 YA + m 16 YA ] & = [ m YA ] [ 1 3 + 1 4 ] & = 7 12 m YA & m =144 10⁻³ ~kg aligned aligned & =A O=B O=C O=D O=10 10⁻² ~m & ~A = ^2 10⁻⁶ ~m ^2 & Y =4.9 10^9 & ~T = 7 12 144 10⁻³ 10 10⁻² ^2 10⁻⁶ 49 10^8 = 7 12 12 1 7 10⁻² 10^8 & =1 10⁻³ & =1 ~ms aligned