The viscosities of a material at various temperatures are given below: Temperature, C 0 20 40 60 80 100 Viscosity, n, poises .....2×10¹¹ .3×10⁹ .....3.5×108 .....5×104 2×10³ ....2×10² a) Draw a curve showing the relation log n and 1/T in Kelvin degrees. b) By using the curve asked in (a), estimate the energy of activation of viscous flow for a temperature range between 20°C and 40°C.

A spherical neutrophil 16µm in diameter is resting as shown in the attached photo. The pressure difference between the inside and outside of the cell is 7.5Pa. a) Draw free body diagrams of the whole cell and one hemisphere of the cell. b) Calculate cortical tension in the cell. In a micropipette aspiration experiment, a suction pressure of 52.5 Pa was used to aspirate the neutrophil membrane. c) Draw free body diagrams of the whole cell under micropipette aspiration and the portion of the cell in the micropipette. What is the diameter of the micropipette tip used to make this hemispherical projection? Next, the micropipette aspiration was stopped, and the cell was treated with Cytochalasin D, an inhibitor of actin polymerization, causing the cortical tension to decrease by half. d) Assuming the pressures inside and outside the cell have not changed, what is the new cell radius? e) If the same micropipette was used to aspirate the cell, what would be the new suction pressure?

2. A car starts from rest and travels 8 sec with an acceleration of a = 4-0.3t, then runs for 33 sec at constant velocity and finally comes to rest by decelerating at 3.125 m/s². a) Determine the velocity of the car after 10 sec. b) Determine the distance traveled by the car during the period of 10 sec. c) Determine the total distance traveled by the car until it stops.

a) An aircraft's instruments measure an air temperature of -10° C and an air pressure of 90 kPa. What is the air density for these conditions? b) What are the pressure and density altitudes of the aircraft? Use the following portion of the standard atmosphere tables. Altitude (m) 75 150 250 300 450 600 750 900 1000 1200 Pressure (KPa) 101.3 100.4 99.5 98.5 97.7 95.9 94.1 92.4 90.8 89.1 87.5 Density (kg/m³) 1.2250 1.2162 1.2075|| 1.1959| 1.1901| 1.1730| 1.1560|| 1.1392 1.1226| 1.1116| 1.0900