[填空题]
The forearm in Fig. 8–45 accelerate/x;3rv*r wqgyvbjp92d /*d f ls a twu.kb,lp2*6hgz:xg ru ia5+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