Question

As shown, a frictionless pulley hangs from a system of springs and a cable. The pulley is equidistant between the two supports attaching the springs to the ceiling. The distance between the supports is d=1.50 m . The cable cannot stretch and its length between the two springs is 1.8 m.

(figure 1)

(FIgure 2)

A)As shown, a mass is hung from the pulley. This mass causes a tensile force of 17.0 N in the cable and the pulley to hang h=130.0 cm from the ceiling. Assume that the pulley has no mass. What is the weight of the mass? (Figure 2)

B)As shown, an object with mass m=4.8 kg is hung from a pulley and spring system. When the object is hung, the tension in the cable is 36.9 N and the pulley is h=147.2 cm below the ceiling.

Because the tensile force is greater than the object’s weight, the pulley cannot be massless as assumed. Find the mass of the pulley.

(Figure 2)

Express your answer to three significant figures and include the appropriate units. For this problem, use g=9.81 m/s2 .

_{Please circle final answer}

d Spring 1 Spring 2 d Spring 2 Spring ww wwwww

Answer 1

50 m h 130 .0 Cm = 3 m 1S/2 =tan J3 Mass cause a 29.g8 Cable こ「子○ N, in FBD oF Pulle Vertical Equilibrium [1 = 4] T A 2T cOso 2TCOS Wa -2メチ× (OS 29.98 9.81 3.0021 3 k m Ans

1.5/2 h-147.2 Cm .472 m 1S/2 tan 1442 FBD OF Pulley T-36.9N vertical Equili baium T=36-9が 270 270 [1= 11 2TCOSO M 2x36.9 X Cos 27 W 65.+563 Total weight WPtmg e 65 7563 65.7563-(4.8 x7.81) WP WP Mass of Pulley, mp 186683 9.81 190 Ka Ans.