Figure gives spring force Fx versus position x for the spring-block arrangement of Fig. 7 -11 The

Question:

Figure gives spring force Fx versus position x for the spring-block arrangement of Fig. 7 -11 The scale is set by F = 160.0 N. We release the block at x = 12 cm. How much work does the spring do on the block when the block moves from xi = + 8.0 cm to

(a) x = +5.0 cm,

(b) x = ?? 5.0 cm,

(d) x = ?? 10.0cm?