Advertisements
Advertisements
प्रश्न
The diagram below shows a pulley arrangement.
(i) In the diagram, mark the direction of the forces due to tension, acting on the pulley P.
(ii) What is the purpose of the pulley Q?
(iii) If the tension is T newton, deduce the relation between T and E.
(iv) Calculate the velocity ratio of the arrangement.
(v) Assuming that the efficiency of the system is 100%, what is the mechanical advantage?
(vi) Calculate the value of E
Advertisements
उत्तर
(ii) The purpose of the pulley Q is to change the direction of application of effort to a convenient direction.
(iii) In the diagram, T = E
(iv) If the free end of the string moves, through the distance x, the load will rise by a distance x/2.
Threfore, V.R = distance moved y the effort arm / distance moved by the load = `"x"/("x"//2) = 2`
(v) In equilibrium,L = 2T and E = T
efficiency = M.A / V. R
or, 1 = `("M ""A")/2`
⇒ M.A = 2
(vi) M.A = `"L"/"E"`
⇒ E = `"L"/("M"."A") = 100/2` = 50 N
APPEARS IN
संबंधित प्रश्न
A block and tackle system has V.R. = 5.
Draw a neat labeled diagram of a system indicating the direction of its load and effort
State two functions of a machine.
State if the following statement is true or false. Correct the statement if it is false.
A single movable pulley is a pulley that has its axis of rotation fixed.
Give reason for the following:
In case of a block and tackle system, the mechanical advantage increases with the increase in the number of pulleys.
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
State two reasons, why the efficiency of a pulley system is not 100 percent?
A pulley is a machine made up of a ______.
| Meera chose to use a block and tackle system of '9' pulleys instead of a single movable pulley to lift a heavy load. |
Why should she connect more number of pulleys in the upper fixed block?
A block and tackle system of pulleys has a velocity ratio of 4.
- Draw a labelled diagram of the system indicating clearly the direction of the load and effort.
- Calculate the potential energy of the load 100 kgf lifted by this pulley to a height 5 m. (g = 10 ms−2)
