[填空题]
A person exerts a force of 55 N on the end of a door 74 cm wide. Wh2/e 9bix-audq ui0tc :-)chpnat is the ma /zd2 5wrp7lwtgnitude of the torque if the f 7 w/w2zltr5pdorce is exerted (a) perpendicular to the door $m \cdot N$ (b) at a 45 $^{\circ} $ angle to the face of the door? $m \cdot N$