Question

A spherical body of mass m and radius r is allowed to fall in a medium of viscosity h. The time in which the velocity of the body increases from zero to 0.63 times the terminal velocity (v) is called time constant (t). Dimensionally t can be represented by –

• A. (a) $\frac{mr^{2}}{6\pi\eta}$
• A. (b) $\sqrt{\frac{6\pi mr\eta}{g^{2}}}$
• A. (c)$\sqrt{\frac{m}{6\pi\eta rv}}$
• A. (d) None of the above

Answer 1

(d)

Sol. T µ m^a r^b h^c