The surface of a solid sphere is covered by a monolayer of receptors for a ligand. When the ligands diffuse to the surface of the sphere, they are captured instantaneously by the receptors. The ligand diffusion coefficient is 1.7*10-9m2/s. Assume the bulk concentration far away from the sphere is constant of 2.5 nM and the sphere radius is 3.1 μm. Find the total ligand flux onto the surface of the sphere. The answer is in the form of A*10-18 mole/s. Please enter the value of A in the box.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Find the kinematic pressure of 160kpa. for air, r-287 j/ kg k. and hair al viscosity of air at a temperature of 50°c and an absolute (10 points) (b) find the dynamic viscosity of air at 110 °c. sutherland constant for air is 111k

What is a monomer? how do they form a ploymer from the view point of chemical bonding?