Question

The boy of mass 45 kg is sliding down the spiral slide at a constant speed such that his position, measured from the top of the chute, has components r 1 t) rad, and z = (-0.51) m, where t is in seconds (Figure 1) Part A .5m, (0.8 Determine the components of force Fr, F, and Fz which the slide exerts on him at the instar t 2 s. Neglect the size of the boy Express your answers using three significant figures separated by commas. P, Fo. 7.17,90.3679,425.8865 Submit Previous Answers Request Answer X Incorrect; Try Again; 2 attempts remaining Term 3: Not quite. Check through your calculations, you may have made a rounding error or used the wrong number of significant figures. Figure 1 of 1 Provide Feedback Next> 2 r 1.5 m

Answer 1

Given mu = 45 kg r = 1.5 m theta = 0.8 t z = -0.5 t t = 2 sec differentiating the component weight acceleration r = 1.5 dr/dt = 0 d^2r/dt^2 = 0 \r\n theta = 0.8 t d theta/dt = 0.8 d^2 theta/dt^2 = 0 z = -0.5 t dz/dt = -0.5 d^2 z/dt^2 = 0 \r\n Radial acceleration a_r = d^2 r/dt^2 - r(d theta/dt)^2 = 0 - 1.5 (0.8)^2 = -0.96 Acceleration in theta - direction a_theta = r d^2 theta/dt^2 + 2 dr/dt middot d theta/dt 1.5 times 0 + 2 times (0) (0.8) a_theta = 0 acceleration in z direction a_z = d^2 z/dt^2 a_z = 0 force Component in radial direction F_r = Mar = 45 x - 0.96 F_r = -43.2 N \r\n force component in theta direction F_theta = M a_theta = 45 times 0 = F_theta = 0 force component