41. explain the difference between homogenous and heterogeneous mixtures. 42. what is the difference between atomic number of an element and its mass number? 43. the big bang theory does not try to explain how the universe was created. what does it explain? 44. why do isotopes of elements have the same atomic number but different mass numbers? 45. why does earth’s moon lack an atmosphere?

Carbon-14 is a radioactive element that undergoes beta decay. which force is responsible for allowing carbon-14 to become stable? electromagnetic gravitational weak nuclear strong nuclear

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

Asteam power plant operates on an ideal reheat rankine cycle between the pressure limits of 15 mpa and 10 kpa. the mass flow rate of steam through the cycle is 12 kg/s. steam enters both stages of the turbine at 500°c. if the moisture content of the steam at the exit of the low-pressure turbine is not to exceed 10 percent, determine (a) the pressure at which reheating takes place, (b) the total rate of heat input in the boiler, and (c) the thermal efficiency of the cycle. also, show the cycle on a t-s diagram with respect to the saturation lines. (2.15 mpa; 45.0 mw; 42.6%)