A 10-meter-long object is traveling at 0.9 c in relation to an observer. Using the length-contraction formula find the observed length in meters (number only, no units).

Select for each of the following statements whether it is correct or incorrect. (a) in an isothermal expansion of an ideal gas. (b) the temperature remains constant. (b) the pressure remains constant. (c) there is work done by the gas. (d) there is heat added to the gas. (e) the change in internal energy equals zero.