Sound waves are mechanical waves in which the particles in the medium vibrate in a direction parallel to the direction of energy transport. identify another name for this type of wave motion.
a) transverse waves
b) pressure waves
c) longitudinal waves
d) electromagnetic waves

During which interval are the persons represented by the graph not moving? a) 0 to 0.5 hrs b) 1.5 to 2 hrs c) 2 to 2.5 hrs d) 4.5 to 5 hrs

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c

Consider a double atwood machine constructed as follows: a mass 4m is suspended from a string that passes over a massless pulley on frictionless bearings. the other end of this string supports a second similar pulley, over which passes a second string supporting a mass of 3m at one end and m at the other. using two suitable generalized coordinates, set up the lagrangian and use the lagrange equations to find the acceleration of the mass 4m when the system is released. explain why the top pulley rotates even though it carries equal weights on each side.