Advertisements
Advertisements
प्रश्न
A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50N. Calculate the Mechanical Advantage and Efficiency of this system.
Advertisements
उत्तर
Load = 120 N; E = 50 N; n = 3
Mechanical advantage of pulley system is
M.A. = `L/E = 120/50` = 2.4
The efficiency of the system is
`eta = ("M.A.")/("V.R.") = (2.4)/n = 2.4/3 = 0.8 = 80%`
APPEARS IN
संबंधित प्रश्न
Select the correct alternative:
A pulley is used because of it
What is the mechanical advantage of an ideal pulley?
Answer the following in short.
Explain the various functions that a machine can perform.
Explain the working of a gear system.
Define the following term in reference to a gear system of Driving gear ?
Differentiate between a single fixed pulley and a single movable pulley.
(a) Fig represents an incomplete diagram of a simple string pulley system. Copy this diagram on a new page and complete it and mark where the effort must be applied to lift the load.
(b) What is the velocity ratio of this system?
(c) If the pulley system is 80% efficient and the load is 720 N, then
(i) What effort must be applied to lift the load?
(ii) What work must be done must be done in lifting the load through a distance of 2 m using this machine?
State two reasons, why the efficiency of a pulley system is not 100 percent?
A pulley system has a velocity ratio of 4 and an efficiency of 90%. Calculate:
(i) the mechanical advantage of the system.
(ii) the effort required to raise a load of 300 N by the system.
A ‘block and tackle’ system used 3 pulleys in the lower block and 4 pulleys in the upper block. What is the ‘velocity ratio’ of this system? If the load is to be lifted by a person capable of applying a maximum effort of 1000 N, what is the maximum load than can be lifted under ideal conditions?
The actual maximum load that gets lifted turns out to be 6300 N. What are the values of the actual M.A. and efficiency of the set-up?
