Advertisements
Advertisements
Question
Draw a diagram of a lever which is always used as a force multiplier. How is the effort arm related to the load arm in such a lever?
Advertisements
Solution
Because the effort arm of a Class II lever is longer than the load arm and the mechanical advantage is always greater than 1, the lever multiplies force.
APPEARS IN
RELATED QUESTIONS
Write down a relation expressing the mechanical advantage of a lever.
A man uses a crowbar of length 1.5 m to raise a load of 75 kgf by putting a sharp edge below the bar at a distance 1 m from his hand.
- Draw a diagram of the arrangement showing the fulcrum (F), load (L) and effort (E) with their directions.
- State the kind of lever.
- Calculate:
- load arm,
- effort arm,
- mechanical advantage and
- the effort needed.
Fig 3.17 below shows a lever in use.
(a) To which class of lever does it belong?
(b) If FA = 80 cm, AB = 20 cm, find its mechanical advantage.
(c) Calculate the value of E.
Give three examples for leavers of the third order.
The following belong to which class of lever?
Human-arm
The following belong to which class of lever?
A fire tongs
The following belong to which class of lever?
Sugar tongs
The following belong to which class of lever?
Fore-arm
State the types (or kinds) of lever, and give two examples of each kind.
A crowbar of length 100 cm is used to lift a load of 5 kgf. It has its fulcrum at a distance of 20 cm from the load. Calculate:
(i) the mechanical advantage of a crowbar and,
(ii) the effort applied at the other end.
