what will be the duration of day and night in hour if the diameter of earth is reduced to half of its original value the mass remain constant?a. 12 b . 6 c. 3 d. 2

moment of inertia(I) is proportional to radius^2 ang. vel (w1) = 2pi/24 i.e pi/12 Let r1 =r r2 =0.5r By law of conservation of angular momentum, I1x w1=I2xw2 I1/I2 = w2/w1 r^2/(0.5 r)^2 = w2/(pi/12) w2=pi/3 so, time period = 6hours