Physics
Answer
A lever is a rigid, straight (or bent) bar which is capable of turning about a fixed axis.
A lever works on the principle of moments, according to which in the equilibrium position of levers, moment of load about the fulcrum must be equal to the moment of effort about the fulcrum and the two moments must be in opposite directions.
Related Questions
(a) State the relationship between mechanical advantage, velocity ratio and efficiency.
(b) Name the term that will not change for a machine of a given design.
State one reason why mechanical advantage is less than the velocity ratio for an actual machine.
Name the three classes of levers and state how are they distinguished. Give two examples of each class.
Both a pair of scissors and a pair of pliers belong to the same class of levers. Name the class of lever. Which one has the mechanical advantage less than 1?