In one type of mass spectrometer, ions having the same velocity move through a uniform magnetic field. The spectrometer is being used to distinguish 12C+ and 14C+ ions that have the same charge. The 12C+ ions move in a circle of diameter 25 cm. (a) What is the diameter of the ...
April 12, 2014
A 2.6x10^3 kg elevator carries a maximum load of 888.1 kg. A constant frictional force of 4.9x10^3 N retards the elevator's motion upward. The acceleration of gravity is 9.81 m.s^2. What minimum power must the motor deliver to lift the fully loaded elevator at a constant ...
December 11, 2011
math - probability
An astronomer wishes to measure on a photograph the distance between the image of a certain star and three other star images nearby. If eight images are nearby, how many choices of the three stars does he have?
March 30, 2010