Steel balls 12 mm in diameter are annealed by heating to 1150 k and then slowly cooling to 400 k in an air environment for which latex: t_{\infty}=325\: kt [infinity] = 325 k and latex: h=20\: \frac{w}{m^2k}h = 20 w m 2 k. assuming the properties of the steel to be k=40 w/m. k, and latex: \rho=7800\: \frac{kg}{m^3}rho = 7800 k g m 3, c= 600 j/kg. k, estimate the time required (in seconds) for the cooling process.

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

When using the ohmmeter function of a digital multimeter, the leads are placed in what position relative to the component being tested? a. parallel b. control c. series d. line

If a particle moves along a path such that r : (3 sin t) m and ? : 2t rad, where t is in seconds. what is the particle's acceleration in m/s in 4 seconds? a)- 16.43 b)- 16.29 c)- 15.21 d)- 13.79