One end of a horizontal string is attached to 
ilc1w:j0n7wki k -e 1ia small-amplitude mechanical 60-Hz vibrator. The string’s mass per unit l
kjl1: i1iww7i-e c0kn ength is $3.9 \times10^{ -4}$ kg/m The string passes over a pulley, a distance  L = 1.50 m away, and weights are hung from this end, Fig. 11–53. What mass m must be hung from this end of the string to produce
 (a) one loop,(round to one decimal place) $\approx$  
  kg 
 (b) two loops,  
  kg 
(c) five loops of a standing wave? Assume the string at the vibrator is a node, which is nearly true. 
  kg 
