(a) In a second-class lever, the ratio of the effort arm to the load arm is ............... (greater than 1 / less than 1).
(b) State one advantage of the combination of one fixed and one movable pulley over a single movable pulley.
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(a) In a second-class lever, the ratio of the effort arm to the load arm is greater than 1.
Reason — In a class II lever the load lies in between the fulcrum and the effort, so the effort arm is always longer than the load arm. Hence the ratio $\frac{\text{effort arm}}{\text{load arm}}$, which is the mechanical advantage, is always greater than 1.
(b) In a single movable pulley the effort has to be applied in the upward direction, which is inconvenient. By adding a fixed pulley to it, the direction of the effort is changed, so that the effort can now be applied in the downward direction, which is much more convenient since the weight of the person applying the effort also helps. The mechanical advantage remains 2 in both cases.