A thin-walled plate separates the interior of a large furnace from surroundings at 300 K. The plate is fabricated from a ceramic material for which diffuse surface behavior may be assumed and the exterior surface is air cooled. With the furnace operating at 2400 K, convection at the interior surface may be neglected. (a) If the temperature of the ceramic plate is not to exceed 1800 K, what is the minimum value of the outside convection coefficient, ho, that must be maintained by the air-cooling system? (b) Compute and plot the plate temperature as a function of ho for 50 ho 250 W/m2 K.
PY 205 Week 3 Notes Chapter 4 and 5 Newton’s Laws 1. Velocities don’t change unless a net force acts upon it (qualitative) 2. The acceleration of a body is directly proportional to the net force acted on it (quantitative) a. Fnet = (mass)(acceleration) 3. Forces occur between two objects – if A exerts a force on B then B exerts a negative force on A. a. Fnet = Fxi +Fyj + Fzk b. The sum of all the forces on x = ma(x) c. The sum of all the force on y = ma(y) Applications of Newton’s laws - Kinetic motion - sliding friction - The force acts opposite to the direction of the object’s velocity - Normal force = shows that the friction force is approximately proportional to the normal force – the