[填空题]
The forearm in Fig. 43di g zc, q*.ldjqt2q8–45 accel xwdpt,4 4mlcr3pr b5.erates a 3.6-kg ball at 7 $m/s^2$ by means of the triceps muscle, as shown. Calculate (a) the torque needed, $m \cdot N$ (b) the force that must be exerted by the triceps muscle. Ignore the mass of the arm. N