35. If water rises in a capillary tube upto 3 cm. What is

the diameter of capillary tube (Surface tension of water = 7.2 ×10–2 N/m)  (a)  9.6×10–4 m (b)  9.6×10–3 m (c)  9.6×10–2 m (d)  9.6×10–1 m Ans. a (56)