Physics
A single fixed pulley and a movable pulley both are separately used to lift a load of 50 kgf to the same height. Compare the efforts applied in an ideal situation.
Machines
125 Likes
Answer
We know that in case of a single fixed pulley, the effort applied is equal to the load.
Hence,
In the case of a movable pulley the effort needed to lift a load is equal to half the load.
Hence, the ratio of efforts applied by the respective pulley is
Therefore, Ef : Em = 2 : 1
Answered By
75 Likes
Related Questions
In a block and tackle system consisting of 3 pulleys, a load of 75 kgf is raised with an effort of 25 kgf.
Find —
(i) the mechanical advantage,
(ii) the velocity ratio, and
(iii) the efficiency.
A woman draws water from a well using a fixed pulley. The mass of the bucket and water together is 6 kg. The force applied by the women is 70 N. Calculate the mechanical advantage. (Take g = 10 m s-2).
A fixed pulley is driven by a 100 kg mass falling at a rate of 8.0 m in 4.0 s. It lifts a load of 75.0 kgf.
Calculate —
(a) The power input to the pulley taking the force of gravity on 1 kg as 10 N.
(b) the efficiency of the pulley, and
(c) the height to which the load is raised in 4.0 s.
A block and tackle system has 5 pulleys. If an effort of 1000 N is needed in the downward direction to raise a load of 4500 N,
Calculate —
(a)The mechanical advantage,
(b)The velocity ratio and,
(c)The efficiency of the system.