A thermocouple is located at the center of a small polymer sphere (density=1200 kg/m3, thermal conductivity=0.21 W/m-K, heat capacity = 1250J/kg-K, radius=0.003 m). The sphere is initially at an equilibrium temperature of 0 degrees celsius. It is suddenly immersed in a hot fluid (100 degrees celsius) at a very high heat transfer coefficient. After how many seconds will the thermocouple show an increase in temperature ?