Question

A spider hangs from a strand of silk whose radius is 4.0 X 10 E-6 m. The density of the silk is 1300 kg/m3(cube). When the spider moves, waves travel along the strand of silk at a speed of 280 m/s. Ignore the mass of the silk strand, and determine the mass of the spider.

Please Help!!!!!!!!!!

Answer 1

Radius r = 4*10^-6 m

Density of the silk ? = 1300 Kg/m^3

Linear mass density ? = ?r^2 ?

                                  = ?(4*10^-6 m)^2 (1300 Kg/m^3)

                                  = 6.53*10^-8 Kg/m

Speed of the wave v = 280 m/s

              Sqrt[mg/?] = 280   

                      mg/? = 78400

                             m = (78400 * 6.53*10^-8)/(9.8 m/s^2)

                                 = 5.224*10^-4 Kg

Mass of the spider m = 5.224*10^-4 Kg or 0.5224 g