Physics
A lever of length 9 cm has its load arm 5 cm long and the effort arm is 9 cm long.
(a) To which class does it belong?
(b) Draw diagram of the lever showing the position of fulcrum F and directions of both the load L and effort E.
(c) What is the mechanical advantage and velocity ratio if the efficiency is 100%?
(d) What will be the mechanical advantage and velocity ratio if the efficiency becomes 50%?
Related Questions
The figure below shows a wheel barrow of mass 15 kg carrying a load of 30 kgf with its centre of gravity at A. The points B and C are the centre of wheel and tip of the handle such that the horizontal distance AB = 20 cm and AC = 40 cm.
Find:
(a) the load arm,
(b) the effort arm,
(c) the mechanical advantage, and
(d) the minimum effort required to keep the leg just off the ground.
A pair of scissors is used to cut a piece of cloth by keeping it at a distance of 8.0 cm from its rivet and applying an effort of 10 kgf by fingers at a distance 2.0 cm from the rivet.
(a) Find: (i) the mechanical advantage of scissors and (ii) the load offered by the cloth.
(b) How does the pair of scissors act - as a force multiplier or as a speed multiplier?
A 4 m long rod of negligible weight is supported at a point 125 cm from its one end and a load of 18 kgf is suspended at a point 60 cm from the support on the shorter arm.
(a) If a weight W is placed at a distance of 250 cm from the support on the longer arm to balance the rod, find W.
(b) If a weight 5 kgf is kept to balance the rod, find its position.
(c) To which class of lever does it belong?
The diagram below shows a lever in use.
(a) To which class of lever does it belong?
(b) Without changing the dimensions of the lever, if the load is shifted towards the fulcrum what happens to the mechanical advantage of the lever?